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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_free_inode(struct inode *inode)
78{
79 kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
80}
81
82static void init_once(void *foo)
83{
84 struct efs_inode_info *ei = (struct efs_inode_info *) foo;
85
86 inode_init_once(&ei->vfs_inode);
87}
88
89static int __init init_inodecache(void)
90{
91 efs_inode_cachep = kmem_cache_create("efs_inode_cache",
92 sizeof(struct efs_inode_info), 0,
93 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
94 SLAB_ACCOUNT, init_once);
95 if (efs_inode_cachep == NULL)
96 return -ENOMEM;
97 return 0;
98}
99
100static void destroy_inodecache(void)
101{
102
103
104
105
106 rcu_barrier();
107 kmem_cache_destroy(efs_inode_cachep);
108}
109
110static int efs_remount(struct super_block *sb, int *flags, char *data)
111{
112 sync_filesystem(sb);
113 *flags |= SB_RDONLY;
114 return 0;
115}
116
117static const struct super_operations efs_superblock_operations = {
118 .alloc_inode = efs_alloc_inode,
119 .free_inode = efs_free_inode,
120 .statfs = efs_statfs,
121 .remount_fs = efs_remount,
122};
123
124static const struct export_operations efs_export_ops = {
125 .fh_to_dentry = efs_fh_to_dentry,
126 .fh_to_parent = efs_fh_to_parent,
127 .get_parent = efs_get_parent,
128};
129
130static int __init init_efs_fs(void) {
131 int err;
132 pr_info(EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
133 err = init_inodecache();
134 if (err)
135 goto out1;
136 err = register_filesystem(&efs_fs_type);
137 if (err)
138 goto out;
139 return 0;
140out:
141 destroy_inodecache();
142out1:
143 return err;
144}
145
146static void __exit exit_efs_fs(void) {
147 unregister_filesystem(&efs_fs_type);
148 destroy_inodecache();
149}
150
151module_init(init_efs_fs)
152module_exit(exit_efs_fs)
153
154static efs_block_t efs_validate_vh(struct volume_header *vh) {
155 int i;
156 __be32 cs, *ui;
157 int csum;
158 efs_block_t sblock = 0;
159 struct pt_types *pt_entry;
160 int pt_type, slice = -1;
161
162 if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
163
164
165
166
167
168 return 0;
169 }
170
171 ui = ((__be32 *) (vh + 1)) - 1;
172 for(csum = 0; ui >= ((__be32 *) vh);) {
173 cs = *ui--;
174 csum += be32_to_cpu(cs);
175 }
176 if (csum) {
177 pr_warn("SGI disklabel: checksum bad, label corrupted\n");
178 return 0;
179 }
180
181#ifdef DEBUG
182 pr_debug("bf: \"%16s\"\n", vh->vh_bootfile);
183
184 for(i = 0; i < NVDIR; i++) {
185 int j;
186 char name[VDNAMESIZE+1];
187
188 for(j = 0; j < VDNAMESIZE; j++) {
189 name[j] = vh->vh_vd[i].vd_name[j];
190 }
191 name[j] = (char) 0;
192
193 if (name[0]) {
194 pr_debug("vh: %8s block: 0x%08x size: 0x%08x\n",
195 name, (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 pr_debug("pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
209 i, (int)be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
210 (int)be32_to_cpu(vh->vh_pt[i].pt_nblks),
211 pt_type, (pt_entry->pt_name) ?
212 pt_entry->pt_name : "unknown");
213 }
214#endif
215 if (IS_EFS(pt_type)) {
216 sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
217 slice = i;
218 }
219 }
220
221 if (slice == -1) {
222 pr_notice("partition table contained no EFS partitions\n");
223#ifdef DEBUG
224 } else {
225 pr_info("using slice %d (type %s, offset 0x%x)\n", slice,
226 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
227 sblock);
228#endif
229 }
230 return sblock;
231}
232
233static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
234
235 if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
236 return -1;
237
238 sb->fs_magic = be32_to_cpu(super->fs_magic);
239 sb->total_blocks = be32_to_cpu(super->fs_size);
240 sb->first_block = be32_to_cpu(super->fs_firstcg);
241 sb->group_size = be32_to_cpu(super->fs_cgfsize);
242 sb->data_free = be32_to_cpu(super->fs_tfree);
243 sb->inode_free = be32_to_cpu(super->fs_tinode);
244 sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
245 sb->total_groups = be16_to_cpu(super->fs_ncg);
246
247 return 0;
248}
249
250static int efs_fill_super(struct super_block *s, void *d, int silent)
251{
252 struct efs_sb_info *sb;
253 struct buffer_head *bh;
254 struct inode *root;
255
256 sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
257 if (!sb)
258 return -ENOMEM;
259 s->s_fs_info = sb;
260
261 s->s_magic = EFS_SUPER_MAGIC;
262 if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
263 pr_err("device does not support %d byte blocks\n",
264 EFS_BLOCKSIZE);
265 return -EINVAL;
266 }
267
268
269 bh = sb_bread(s, 0);
270
271 if (!bh) {
272 pr_err("cannot read volume header\n");
273 return -EIO;
274 }
275
276
277
278
279
280
281 sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
282 brelse(bh);
283
284 if (sb->fs_start == -1) {
285 return -EINVAL;
286 }
287
288 bh = sb_bread(s, sb->fs_start + EFS_SUPER);
289 if (!bh) {
290 pr_err("cannot read superblock\n");
291 return -EIO;
292 }
293
294 if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
295#ifdef DEBUG
296 pr_warn("invalid superblock at block %u\n",
297 sb->fs_start + EFS_SUPER);
298#endif
299 brelse(bh);
300 return -EINVAL;
301 }
302 brelse(bh);
303
304 if (!sb_rdonly(s)) {
305#ifdef DEBUG
306 pr_info("forcing read-only mode\n");
307#endif
308 s->s_flags |= SB_RDONLY;
309 }
310 s->s_op = &efs_superblock_operations;
311 s->s_export_op = &efs_export_ops;
312 root = efs_iget(s, EFS_ROOTINODE);
313 if (IS_ERR(root)) {
314 pr_err("get root inode failed\n");
315 return PTR_ERR(root);
316 }
317
318 s->s_root = d_make_root(root);
319 if (!(s->s_root)) {
320 pr_err("get root dentry failed\n");
321 return -ENOMEM;
322 }
323
324 return 0;
325}
326
327static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
328 struct super_block *sb = dentry->d_sb;
329 struct efs_sb_info *sbi = SUPER_INFO(sb);
330 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
331
332 buf->f_type = EFS_SUPER_MAGIC;
333 buf->f_bsize = EFS_BLOCKSIZE;
334 buf->f_blocks = sbi->total_groups *
335 (sbi->group_size - sbi->inode_blocks);
336 buf->f_bfree = sbi->data_free;
337 buf->f_bavail = sbi->data_free;
338 buf->f_files = sbi->total_groups *
339 sbi->inode_blocks *
340 (EFS_BLOCKSIZE / sizeof(struct efs_dinode));
341 buf->f_ffree = sbi->inode_free;
342 buf->f_fsid.val[0] = (u32)id;
343 buf->f_fsid.val[1] = (u32)(id >> 32);
344 buf->f_namelen = EFS_MAXNAMELEN;
345
346 return 0;
347}
348
349
