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8#include <linux/module.h>
9#include <linux/types.h>
10#include <linux/string.h>
11#include <linux/fs.h>
12#include <linux/fs_context.h>
13#include <linux/init.h>
14#include <linux/slab.h>
15#include <linux/seq_file.h>
16#include <linux/magic.h>
17
18#include <asm/openprom.h>
19#include <asm/oplib.h>
20#include <asm/prom.h>
21#include <linux/uaccess.h>
22
23static DEFINE_MUTEX(op_mutex);
24
25#define OPENPROM_ROOT_INO 0
26
27enum op_inode_type {
28 op_inode_node,
29 op_inode_prop,
30};
31
32union op_inode_data {
33 struct device_node *node;
34 struct property *prop;
35};
36
37struct op_inode_info {
38 struct inode vfs_inode;
39 enum op_inode_type type;
40 union op_inode_data u;
41};
42
43static struct inode *openprom_iget(struct super_block *sb, ino_t ino);
44
45static inline struct op_inode_info *OP_I(struct inode *inode)
46{
47 return container_of(inode, struct op_inode_info, vfs_inode);
48}
49
50static int is_string(unsigned char *p, int len)
51{
52 int i;
53
54 for (i = 0; i < len; i++) {
55 unsigned char val = p[i];
56
57 if ((i && !val) ||
58 (val >= ' ' && val <= '~'))
59 continue;
60
61 return 0;
62 }
63
64 return 1;
65}
66
67static int property_show(struct seq_file *f, void *v)
68{
69 struct property *prop = f->private;
70 void *pval;
71 int len;
72
73 len = prop->length;
74 pval = prop->value;
75
76 if (is_string(pval, len)) {
77 while (len > 0) {
78 int n = strlen(pval);
79
80 seq_printf(f, "%s", (char *) pval);
81
82
83 pval += n + 1;
84 len -= n + 1;
85
86 if (len > 0)
87 seq_printf(f, " + ");
88 }
89 } else {
90 if (len & 3) {
91 while (len) {
92 len--;
93 if (len)
94 seq_printf(f, "%02x.",
95 *(unsigned char *) pval);
96 else
97 seq_printf(f, "%02x",
98 *(unsigned char *) pval);
99 pval++;
100 }
101 } else {
102 while (len >= 4) {
103 len -= 4;
104
105 if (len)
106 seq_printf(f, "%08x.",
107 *(unsigned int *) pval);
108 else
109 seq_printf(f, "%08x",
110 *(unsigned int *) pval);
111 pval += 4;
112 }
113 }
114 }
115 seq_printf(f, "\n");
116
117 return 0;
118}
119
120static void *property_start(struct seq_file *f, loff_t *pos)
121{
122 if (*pos == 0)
123 return pos;
124 return NULL;
125}
126
127static void *property_next(struct seq_file *f, void *v, loff_t *pos)
128{
129 (*pos)++;
130 return NULL;
131}
132
133static void property_stop(struct seq_file *f, void *v)
134{
135
136}
137
138static const struct seq_operations property_op = {
139 .start = property_start,
140 .next = property_next,
141 .stop = property_stop,
142 .show = property_show
143};
144
145static int property_open(struct inode *inode, struct file *file)
146{
147 struct op_inode_info *oi = OP_I(inode);
148 int ret;
149
150 BUG_ON(oi->type != op_inode_prop);
151
152 ret = seq_open(file, &property_op);
153 if (!ret) {
154 struct seq_file *m = file->private_data;
155 m->private = oi->u.prop;
156 }
157 return ret;
158}
159
160static const struct file_operations openpromfs_prop_ops = {
161 .open = property_open,
162 .read = seq_read,
163 .llseek = seq_lseek,
164 .release = seq_release,
165};
166
167static int openpromfs_readdir(struct file *, struct dir_context *);
168
169static const struct file_operations openprom_operations = {
170 .read = generic_read_dir,
171 .iterate_shared = openpromfs_readdir,
172 .llseek = generic_file_llseek,
173};
174
175static struct dentry *openpromfs_lookup(struct inode *, struct dentry *, unsigned int);
176
177static const struct inode_operations openprom_inode_operations = {
178 .lookup = openpromfs_lookup,
179};
180
181static struct dentry *openpromfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
182{
183 struct op_inode_info *ent_oi, *oi = OP_I(dir);
184 struct device_node *dp, *child;
185 struct property *prop;
186 enum op_inode_type ent_type;
187 union op_inode_data ent_data;
188 const char *name;
189 struct inode *inode;
190 unsigned int ino;
191 int len;
192
193 BUG_ON(oi->type != op_inode_node);
194
195 dp = oi->u.node;
196
197 name = dentry->d_name.name;
198 len = dentry->d_name.len;
199
200 mutex_lock(&op_mutex);
201
202 child = dp->child;
203 while (child) {
204 const char *node_name = kbasename(child->full_name);
205 int n = strlen(node_name);
206
207 if (len == n &&
208 !strncmp(node_name, name, len)) {
209 ent_type = op_inode_node;
210 ent_data.node = child;
211 ino = child->unique_id;
212 goto found;
213 }
214 child = child->sibling;
215 }
216
217 prop = dp->properties;
218 while (prop) {
219 int n = strlen(prop->name);
220
221 if (len == n && !strncmp(prop->name, name, len)) {
222 ent_type = op_inode_prop;
223 ent_data.prop = prop;
224 ino = prop->unique_id;
225 goto found;
226 }
227
228 prop = prop->next;
229 }
230
231 mutex_unlock(&op_mutex);
232 return ERR_PTR(-ENOENT);
233
234found:
235 inode = openprom_iget(dir->i_sb, ino);
236 mutex_unlock(&op_mutex);
237 if (IS_ERR(inode))
238 return ERR_CAST(inode);
239 ent_oi = OP_I(inode);
240 ent_oi->type = ent_type;
241 ent_oi->u = ent_data;
242
243 switch (ent_type) {
244 case op_inode_node:
245 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
246 inode->i_op = &openprom_inode_operations;
247 inode->i_fop = &openprom_operations;
248 set_nlink(inode, 2);
249 break;
250 case op_inode_prop:
251 if (of_node_name_eq(dp, "options") && (len == 17) &&
252 !strncmp (name, "security-password", 17))
253 inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
254 else
255 inode->i_mode = S_IFREG | S_IRUGO;
256 inode->i_fop = &openpromfs_prop_ops;
257 set_nlink(inode, 1);
258 inode->i_size = ent_oi->u.prop->length;
259 break;
260 }
261
262 return d_splice_alias(inode, dentry);
263}
264
265static int openpromfs_readdir(struct file *file, struct dir_context *ctx)
266{
267 struct inode *inode = file_inode(file);
268 struct op_inode_info *oi = OP_I(inode);
269 struct device_node *dp = oi->u.node;
270 struct device_node *child;
271 struct property *prop;
272 int i;
273
274 mutex_lock(&op_mutex);
275
276 if (ctx->pos == 0) {
277 if (!dir_emit(ctx, ".", 1, inode->i_ino, DT_DIR))
278 goto out;
279 ctx->pos = 1;
280 }
281 if (ctx->pos == 1) {
282 if (!dir_emit(ctx, "..", 2,
283 (dp->parent == NULL ?
284 OPENPROM_ROOT_INO :
285 dp->parent->unique_id), DT_DIR))
286 goto out;
287 ctx->pos = 2;
288 }
289 i = ctx->pos - 2;
290
291
292 child = dp->child;
293 while (i && child) {
294 child = child->sibling;
295 i--;
296 }
297 while (child) {
298 if (!dir_emit(ctx,
299 kbasename(child->full_name),
300 strlen(kbasename(child->full_name)),
301 child->unique_id, DT_DIR))
302 goto out;
303
304 ctx->pos++;
305 child = child->sibling;
306 }
307
308
309 prop = dp->properties;
310 while (i && prop) {
311 prop = prop->next;
312 i--;
313 }
314 while (prop) {
315 if (!dir_emit(ctx, prop->name, strlen(prop->name),
316 prop->unique_id, DT_REG))
317 goto out;
318
319 ctx->pos++;
320 prop = prop->next;
321 }
322
323out:
324 mutex_unlock(&op_mutex);
325 return 0;
326}
327
328static struct kmem_cache *op_inode_cachep;
329
330static struct inode *openprom_alloc_inode(struct super_block *sb)
331{
332 struct op_inode_info *oi;
333
334 oi = kmem_cache_alloc(op_inode_cachep, GFP_KERNEL);
335 if (!oi)
336 return NULL;
337
338 return &oi->vfs_inode;
339}
340
341static void openprom_free_inode(struct inode *inode)
342{
343 kmem_cache_free(op_inode_cachep, OP_I(inode));
344}
345
346static struct inode *openprom_iget(struct super_block *sb, ino_t ino)
347{
348 struct inode *inode;
349
350 inode = iget_locked(sb, ino);
351 if (!inode)
352 return ERR_PTR(-ENOMEM);
353 if (inode->i_state & I_NEW) {
354 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
355 if (inode->i_ino == OPENPROM_ROOT_INO) {
356 inode->i_op = &openprom_inode_operations;
357 inode->i_fop = &openprom_operations;
358 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
359 }
360 unlock_new_inode(inode);
361 }
362 return inode;
363}
364
365static int openprom_remount(struct super_block *sb, int *flags, char *data)
366{
367 sync_filesystem(sb);
368 *flags |= SB_NOATIME;
369 return 0;
370}
371
372static const struct super_operations openprom_sops = {
373 .alloc_inode = openprom_alloc_inode,
374 .free_inode = openprom_free_inode,
375 .statfs = simple_statfs,
376 .remount_fs = openprom_remount,
377};
378
379static int openprom_fill_super(struct super_block *s, struct fs_context *fc)
380{
381 struct inode *root_inode;
382 struct op_inode_info *oi;
383 int ret;
384
385 s->s_flags |= SB_NOATIME;
386 s->s_blocksize = 1024;
387 s->s_blocksize_bits = 10;
388 s->s_magic = OPENPROM_SUPER_MAGIC;
389 s->s_op = &openprom_sops;
390 s->s_time_gran = 1;
391 root_inode = openprom_iget(s, OPENPROM_ROOT_INO);
392 if (IS_ERR(root_inode)) {
393 ret = PTR_ERR(root_inode);
394 goto out_no_root;
395 }
396
397 oi = OP_I(root_inode);
398 oi->type = op_inode_node;
399 oi->u.node = of_find_node_by_path("/");
400
401 s->s_root = d_make_root(root_inode);
402 if (!s->s_root)
403 goto out_no_root_dentry;
404 return 0;
405
406out_no_root_dentry:
407 ret = -ENOMEM;
408out_no_root:
409 printk("openprom_fill_super: get root inode failed\n");
410 return ret;
411}
412
413static int openpromfs_get_tree(struct fs_context *fc)
414{
415 return get_tree_single(fc, openprom_fill_super);
416}
417
418static const struct fs_context_operations openpromfs_context_ops = {
419 .get_tree = openpromfs_get_tree,
420};
421
422static int openpromfs_init_fs_context(struct fs_context *fc)
423{
424 fc->ops = &openpromfs_context_ops;
425 return 0;
426}
427
428static struct file_system_type openprom_fs_type = {
429 .owner = THIS_MODULE,
430 .name = "openpromfs",
431 .init_fs_context = openpromfs_init_fs_context,
432 .kill_sb = kill_anon_super,
433};
434MODULE_ALIAS_FS("openpromfs");
435
436static void op_inode_init_once(void *data)
437{
438 struct op_inode_info *oi = (struct op_inode_info *) data;
439
440 inode_init_once(&oi->vfs_inode);
441}
442
443static int __init init_openprom_fs(void)
444{
445 int err;
446
447 op_inode_cachep = kmem_cache_create("op_inode_cache",
448 sizeof(struct op_inode_info),
449 0,
450 (SLAB_RECLAIM_ACCOUNT |
451 SLAB_MEM_SPREAD | SLAB_ACCOUNT),
452 op_inode_init_once);
453 if (!op_inode_cachep)
454 return -ENOMEM;
455
456 err = register_filesystem(&openprom_fs_type);
457 if (err)
458 kmem_cache_destroy(op_inode_cachep);
459
460 return err;
461}
462
463static void __exit exit_openprom_fs(void)
464{
465 unregister_filesystem(&openprom_fs_type);
466
467
468
469
470 rcu_barrier();
471 kmem_cache_destroy(op_inode_cachep);
472}
473
474module_init(init_openprom_fs)
475module_exit(exit_openprom_fs)
476MODULE_LICENSE("GPL");
477
