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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 void efs_kill_sb(struct super_block *s)
30{
31 struct efs_sb_info *sbi = SUPER_INFO(s);
32 kill_block_super(s);
33 kfree(sbi);
34}
35
36static struct file_system_type efs_fs_type = {
37 .owner = THIS_MODULE,
38 .name = "efs",
39 .mount = efs_mount,
40 .kill_sb = efs_kill_sb,
41 .fs_flags = FS_REQUIRES_DEV,
42};
43MODULE_ALIAS_FS("efs");
44
45static struct pt_types sgi_pt_types[] = {
46 {0x00, "SGI vh"},
47 {0x01, "SGI trkrepl"},
48 {0x02, "SGI secrepl"},
49 {0x03, "SGI raw"},
50 {0x04, "SGI bsd"},
51 {SGI_SYSV, "SGI sysv"},
52 {0x06, "SGI vol"},
53 {SGI_EFS, "SGI efs"},
54 {0x08, "SGI lv"},
55 {0x09, "SGI rlv"},
56 {0x0A, "SGI xfs"},
57 {0x0B, "SGI xfslog"},
58 {0x0C, "SGI xlv"},
59 {0x82, "Linux swap"},
60 {0x83, "Linux native"},
61 {0, NULL}
62};
63
64
65static struct kmem_cache * efs_inode_cachep;
66
67static struct inode *efs_alloc_inode(struct super_block *sb)
68{
69 struct efs_inode_info *ei;
70 ei = kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
71 if (!ei)
72 return NULL;
73 return &ei->vfs_inode;
74}
75
76static void efs_i_callback(struct rcu_head *head)
77{
78 struct inode *inode = container_of(head, struct inode, i_rcu);
79 kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
80}
81
82static void efs_destroy_inode(struct inode *inode)
83{
84 call_rcu(&inode->i_rcu, efs_i_callback);
85}
86
87static void init_once(void *foo)
88{
89 struct efs_inode_info *ei = (struct efs_inode_info *) foo;
90
91 inode_init_once(&ei->vfs_inode);
92}
93
94static int __init init_inodecache(void)
95{
96 efs_inode_cachep = kmem_cache_create("efs_inode_cache",
97 sizeof(struct efs_inode_info),
98 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
99 init_once);
100 if (efs_inode_cachep == NULL)
101 return -ENOMEM;
102 return 0;
103}
104
105static void destroy_inodecache(void)
106{
107
108
109
110
111 rcu_barrier();
112 kmem_cache_destroy(efs_inode_cachep);
113}
114
115static int efs_remount(struct super_block *sb, int *flags, char *data)
116{
117 sync_filesystem(sb);
118 *flags |= MS_RDONLY;
119 return 0;
120}
121
122static const struct super_operations efs_superblock_operations = {
123 .alloc_inode = efs_alloc_inode,
124 .destroy_inode = efs_destroy_inode,
125 .statfs = efs_statfs,
126 .remount_fs = efs_remount,
127};
128
129static const struct export_operations efs_export_ops = {
130 .fh_to_dentry = efs_fh_to_dentry,
131 .fh_to_parent = efs_fh_to_parent,
132 .get_parent = efs_get_parent,
133};
134
135static int __init init_efs_fs(void) {
136 int err;
137 pr_info(EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
138 err = init_inodecache();
139 if (err)
140 goto out1;
141 err = register_filesystem(&efs_fs_type);
142 if (err)
143 goto out;
144 return 0;
145out:
146 destroy_inodecache();
147out1:
148 return err;
149}
150
151static void __exit exit_efs_fs(void) {
152 unregister_filesystem(&efs_fs_type);
153 destroy_inodecache();
154}
155
156module_init(init_efs_fs)
157module_exit(exit_efs_fs)
158
159static efs_block_t efs_validate_vh(struct volume_header *vh) {
160 int i;
161 __be32 cs, *ui;
162 int csum;
163 efs_block_t sblock = 0;
164 struct pt_types *pt_entry;
165 int pt_type, slice = -1;
166
167 if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
168
169
170
171
172
173 return 0;
174 }
175
176 ui = ((__be32 *) (vh + 1)) - 1;
177 for(csum = 0; ui >= ((__be32 *) vh);) {
178 cs = *ui--;
179 csum += be32_to_cpu(cs);
180 }
181 if (csum) {
182 pr_warn("SGI disklabel: checksum bad, label corrupted\n");
183 return 0;
184 }
185
186#ifdef DEBUG
187 pr_debug("bf: \"%16s\"\n", vh->vh_bootfile);
188
189 for(i = 0; i < NVDIR; i++) {
190 int j;
191 char name[VDNAMESIZE+1];
192
193 for(j = 0; j < VDNAMESIZE; j++) {
194 name[j] = vh->vh_vd[i].vd_name[j];
195 }
196 name[j] = (char) 0;
197
198 if (name[0]) {
199 pr_debug("vh: %8s block: 0x%08x size: 0x%08x\n",
200 name, (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 pr_debug("pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
214 i, (int)be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
215 (int)be32_to_cpu(vh->vh_pt[i].pt_nblks),
216 pt_type, (pt_entry->pt_name) ?
217 pt_entry->pt_name : "unknown");
218 }
219#endif
220 if (IS_EFS(pt_type)) {
221 sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
222 slice = i;
223 }
224 }
225
226 if (slice == -1) {
227 pr_notice("partition table contained no EFS partitions\n");
228#ifdef DEBUG
229 } else {
230 pr_info("using slice %d (type %s, offset 0x%x)\n", slice,
231 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
232 sblock);
233#endif
234 }
235 return sblock;
236}
237
238static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
239
240 if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
241 return -1;
242
243 sb->fs_magic = be32_to_cpu(super->fs_magic);
244 sb->total_blocks = be32_to_cpu(super->fs_size);
245 sb->first_block = be32_to_cpu(super->fs_firstcg);
246 sb->group_size = be32_to_cpu(super->fs_cgfsize);
247 sb->data_free = be32_to_cpu(super->fs_tfree);
248 sb->inode_free = be32_to_cpu(super->fs_tinode);
249 sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
250 sb->total_groups = be16_to_cpu(super->fs_ncg);
251
252 return 0;
253}
254
255static int efs_fill_super(struct super_block *s, void *d, int silent)
256{
257 struct efs_sb_info *sb;
258 struct buffer_head *bh;
259 struct inode *root;
260
261 sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
262 if (!sb)
263 return -ENOMEM;
264 s->s_fs_info = sb;
265
266 s->s_magic = EFS_SUPER_MAGIC;
267 if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
268 pr_err("device does not support %d byte blocks\n",
269 EFS_BLOCKSIZE);
270 return -EINVAL;
271 }
272
273
274 bh = sb_bread(s, 0);
275
276 if (!bh) {
277 pr_err("cannot read volume header\n");
278 return -EINVAL;
279 }
280
281
282
283
284
285
286 sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
287 brelse(bh);
288
289 if (sb->fs_start == -1) {
290 return -EINVAL;
291 }
292
293 bh = sb_bread(s, sb->fs_start + EFS_SUPER);
294 if (!bh) {
295 pr_err("cannot read superblock\n");
296 return -EINVAL;
297 }
298
299 if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
300#ifdef DEBUG
301 pr_warn("invalid superblock at block %u\n",
302 sb->fs_start + EFS_SUPER);
303#endif
304 brelse(bh);
305 return -EINVAL;
306 }
307 brelse(bh);
308
309 if (!(s->s_flags & MS_RDONLY)) {
310#ifdef DEBUG
311 pr_info("forcing read-only mode\n");
312#endif
313 s->s_flags |= MS_RDONLY;
314 }
315 s->s_op = &efs_superblock_operations;
316 s->s_export_op = &efs_export_ops;
317 root = efs_iget(s, EFS_ROOTINODE);
318 if (IS_ERR(root)) {
319 pr_err("get root inode failed\n");
320 return PTR_ERR(root);
321 }
322
323 s->s_root = d_make_root(root);
324 if (!(s->s_root)) {
325 pr_err("get root dentry failed\n");
326 return -ENOMEM;
327 }
328
329 return 0;
330}
331
332static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
333 struct super_block *sb = dentry->d_sb;
334 struct efs_sb_info *sbi = SUPER_INFO(sb);
335 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
336
337 buf->f_type = EFS_SUPER_MAGIC;
338 buf->f_bsize = EFS_BLOCKSIZE;
339 buf->f_blocks = sbi->total_groups *
340 (sbi->group_size - sbi->inode_blocks);
341 buf->f_bfree = sbi->data_free;
342 buf->f_bavail = sbi->data_free;
343 buf->f_files = sbi->total_groups *
344 sbi->inode_blocks *
345 (EFS_BLOCKSIZE / sizeof(struct efs_dinode));
346 buf->f_ffree = sbi->inode_free;
347 buf->f_fsid.val[0] = (u32)id;
348 buf->f_fsid.val[1] = (u32)(id >> 32);
349 buf->f_namelen = EFS_MAXNAMELEN;
350
351 return 0;
352}
353
354
