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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};
36
37static struct pt_types sgi_pt_types[] = {
38 {0x00, "SGI vh"},
39 {0x01, "SGI trkrepl"},
40 {0x02, "SGI secrepl"},
41 {0x03, "SGI raw"},
42 {0x04, "SGI bsd"},
43 {SGI_SYSV, "SGI sysv"},
44 {0x06, "SGI vol"},
45 {SGI_EFS, "SGI efs"},
46 {0x08, "SGI lv"},
47 {0x09, "SGI rlv"},
48 {0x0A, "SGI xfs"},
49 {0x0B, "SGI xfslog"},
50 {0x0C, "SGI xlv"},
51 {0x82, "Linux swap"},
52 {0x83, "Linux native"},
53 {0, NULL}
54};
55
56
57static struct kmem_cache * efs_inode_cachep;
58
59static struct inode *efs_alloc_inode(struct super_block *sb)
60{
61 struct efs_inode_info *ei;
62 ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
63 if (!ei)
64 return NULL;
65 return &ei->vfs_inode;
66}
67
68static void efs_i_callback(struct rcu_head *head)
69{
70 struct inode *inode = container_of(head, struct inode, i_rcu);
71 INIT_LIST_HEAD(&inode->i_dentry);
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 kmem_cache_destroy(efs_inode_cachep);
101}
102
103static void efs_put_super(struct super_block *s)
104{
105 kfree(s->s_fs_info);
106 s->s_fs_info = NULL;
107}
108
109static int efs_remount(struct super_block *sb, int *flags, char *data)
110{
111 *flags |= MS_RDONLY;
112 return 0;
113}
114
115static const struct super_operations efs_superblock_operations = {
116 .alloc_inode = efs_alloc_inode,
117 .destroy_inode = efs_destroy_inode,
118 .put_super = efs_put_super,
119 .statfs = efs_statfs,
120 .remount_fs = efs_remount,
121};
122
123static const struct export_operations efs_export_ops = {
124 .fh_to_dentry = efs_fh_to_dentry,
125 .fh_to_parent = efs_fh_to_parent,
126 .get_parent = efs_get_parent,
127};
128
129static int __init init_efs_fs(void) {
130 int err;
131 printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
132 err = init_inodecache();
133 if (err)
134 goto out1;
135 err = register_filesystem(&efs_fs_type);
136 if (err)
137 goto out;
138 return 0;
139out:
140 destroy_inodecache();
141out1:
142 return err;
143}
144
145static void __exit exit_efs_fs(void) {
146 unregister_filesystem(&efs_fs_type);
147 destroy_inodecache();
148}
149
150module_init(init_efs_fs)
151module_exit(exit_efs_fs)
152
153static efs_block_t efs_validate_vh(struct volume_header *vh) {
154 int i;
155 __be32 cs, *ui;
156 int csum;
157 efs_block_t sblock = 0;
158 struct pt_types *pt_entry;
159 int pt_type, slice = -1;
160
161 if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
162
163
164
165
166
167 return 0;
168 }
169
170 ui = ((__be32 *) (vh + 1)) - 1;
171 for(csum = 0; ui >= ((__be32 *) vh);) {
172 cs = *ui--;
173 csum += be32_to_cpu(cs);
174 }
175 if (csum) {
176 printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
177 return 0;
178 }
179
180#ifdef DEBUG
181 printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);
182
183 for(i = 0; i < NVDIR; i++) {
184 int j;
185 char name[VDNAMESIZE+1];
186
187 for(j = 0; j < VDNAMESIZE; j++) {
188 name[j] = vh->vh_vd[i].vd_name[j];
189 }
190 name[j] = (char) 0;
191
192 if (name[0]) {
193 printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
194 name,
195 (int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
196 (int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
197 }
198 }
199#endif
200
201 for(i = 0; i < NPARTAB; i++) {
202 pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
203 for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
204 if (pt_type == pt_entry->pt_type) break;
205 }
206#ifdef DEBUG
207 if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
208 printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
209 i,
210 (int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
211 (int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
212 pt_type,
213 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
214 }
215#endif
216 if (IS_EFS(pt_type)) {
217 sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
218 slice = i;
219 }
220 }
221
222 if (slice == -1) {
223 printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
224#ifdef DEBUG
225 } else {
226 printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
227 slice,
228 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
229 sblock);
230#endif
231 }
232 return sblock;
233}
234
235static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
236
237 if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
238 return -1;
239
240 sb->fs_magic = be32_to_cpu(super->fs_magic);
241 sb->total_blocks = be32_to_cpu(super->fs_size);
242 sb->first_block = be32_to_cpu(super->fs_firstcg);
243 sb->group_size = be32_to_cpu(super->fs_cgfsize);
244 sb->data_free = be32_to_cpu(super->fs_tfree);
245 sb->inode_free = be32_to_cpu(super->fs_tinode);
246 sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
247 sb->total_groups = be16_to_cpu(super->fs_ncg);
248
249 return 0;
250}
251
252static int efs_fill_super(struct super_block *s, void *d, int silent)
253{
254 struct efs_sb_info *sb;
255 struct buffer_head *bh;
256 struct inode *root;
257 int ret = -EINVAL;
258
259 sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
260 if (!sb)
261 return -ENOMEM;
262 s->s_fs_info = sb;
263
264 s->s_magic = EFS_SUPER_MAGIC;
265 if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
266 printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
267 EFS_BLOCKSIZE);
268 goto out_no_fs_ul;
269 }
270
271
272 bh = sb_bread(s, 0);
273
274 if (!bh) {
275 printk(KERN_ERR "EFS: cannot read volume header\n");
276 goto out_no_fs_ul;
277 }
278
279
280
281
282
283
284 sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
285 brelse(bh);
286
287 if (sb->fs_start == -1) {
288 goto out_no_fs_ul;
289 }
290
291 bh = sb_bread(s, sb->fs_start + EFS_SUPER);
292 if (!bh) {
293 printk(KERN_ERR "EFS: cannot read superblock\n");
294 goto out_no_fs_ul;
295 }
296
297 if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
298#ifdef DEBUG
299 printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
300#endif
301 brelse(bh);
302 goto out_no_fs_ul;
303 }
304 brelse(bh);
305
306 if (!(s->s_flags & MS_RDONLY)) {
307#ifdef DEBUG
308 printk(KERN_INFO "EFS: forcing read-only mode\n");
309#endif
310 s->s_flags |= MS_RDONLY;
311 }
312 s->s_op = &efs_superblock_operations;
313 s->s_export_op = &efs_export_ops;
314 root = efs_iget(s, EFS_ROOTINODE);
315 if (IS_ERR(root)) {
316 printk(KERN_ERR "EFS: get root inode failed\n");
317 ret = PTR_ERR(root);
318 goto out_no_fs;
319 }
320
321 s->s_root = d_alloc_root(root);
322 if (!(s->s_root)) {
323 printk(KERN_ERR "EFS: get root dentry failed\n");
324 iput(root);
325 ret = -ENOMEM;
326 goto out_no_fs;
327 }
328
329 return 0;
330
331out_no_fs_ul:
332out_no_fs:
333 s->s_fs_info = NULL;
334 kfree(sb);
335 return ret;
336}
337
338static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
339 struct super_block *sb = dentry->d_sb;
340 struct efs_sb_info *sbi = SUPER_INFO(sb);
341 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
342
343 buf->f_type = EFS_SUPER_MAGIC;
344 buf->f_bsize = EFS_BLOCKSIZE;
345 buf->f_blocks = sbi->total_groups *
346 (sbi->group_size - sbi->inode_blocks);
347 buf->f_bfree = sbi->data_free;
348 buf->f_bavail = sbi->data_free;
349 buf->f_files = sbi->total_groups *
350 sbi->inode_blocks *
351 (EFS_BLOCKSIZE / sizeof(struct efs_dinode));
352 buf->f_ffree = sbi->inode_free;
353 buf->f_fsid.val[0] = (u32)id;
354 buf->f_fsid.val[1] = (u32)(id >> 32);
355 buf->f_namelen = EFS_MAXNAMELEN;
356
357 return 0;
358}
359
360
