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1/*
2 * linux/fs/adfs/dir.c
3 *
4 * Copyright (C) 1999-2000 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Common directory handling for ADFS
11 */
12#include "adfs.h"
13
14/*
15 * For future. This should probably be per-directory.
16 */
17static DEFINE_RWLOCK(adfs_dir_lock);
18
19static int
20adfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
21{
22 struct inode *inode = filp->f_path.dentry->d_inode;
23 struct super_block *sb = inode->i_sb;
24 struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
25 struct object_info obj;
26 struct adfs_dir dir;
27 int ret = 0;
28
29 if (filp->f_pos >> 32)
30 goto out;
31
32 ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
33 if (ret)
34 goto out;
35
36 switch ((unsigned long)filp->f_pos) {
37 case 0:
38 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
39 goto free_out;
40 filp->f_pos += 1;
41
42 case 1:
43 if (filldir(dirent, "..", 2, 1, dir.parent_id, DT_DIR) < 0)
44 goto free_out;
45 filp->f_pos += 1;
46
47 default:
48 break;
49 }
50
51 read_lock(&adfs_dir_lock);
52
53 ret = ops->setpos(&dir, filp->f_pos - 2);
54 if (ret)
55 goto unlock_out;
56 while (ops->getnext(&dir, &obj) == 0) {
57 if (filldir(dirent, obj.name, obj.name_len,
58 filp->f_pos, obj.file_id, DT_UNKNOWN) < 0)
59 goto unlock_out;
60 filp->f_pos += 1;
61 }
62
63unlock_out:
64 read_unlock(&adfs_dir_lock);
65
66free_out:
67 ops->free(&dir);
68
69out:
70 return ret;
71}
72
73int
74adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait)
75{
76 int ret = -EINVAL;
77#ifdef CONFIG_ADFS_FS_RW
78 struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
79 struct adfs_dir dir;
80
81 printk(KERN_INFO "adfs_dir_update: object %06X in dir %06X\n",
82 obj->file_id, obj->parent_id);
83
84 if (!ops->update) {
85 ret = -EINVAL;
86 goto out;
87 }
88
89 ret = ops->read(sb, obj->parent_id, 0, &dir);
90 if (ret)
91 goto out;
92
93 write_lock(&adfs_dir_lock);
94 ret = ops->update(&dir, obj);
95 write_unlock(&adfs_dir_lock);
96
97 if (wait) {
98 int err = ops->sync(&dir);
99 if (!ret)
100 ret = err;
101 }
102
103 ops->free(&dir);
104out:
105#endif
106 return ret;
107}
108
109static int
110adfs_match(struct qstr *name, struct object_info *obj)
111{
112 int i;
113
114 if (name->len != obj->name_len)
115 return 0;
116
117 for (i = 0; i < name->len; i++) {
118 char c1, c2;
119
120 c1 = name->name[i];
121 c2 = obj->name[i];
122
123 if (c1 >= 'A' && c1 <= 'Z')
124 c1 += 'a' - 'A';
125 if (c2 >= 'A' && c2 <= 'Z')
126 c2 += 'a' - 'A';
127
128 if (c1 != c2)
129 return 0;
130 }
131 return 1;
132}
133
134static int
135adfs_dir_lookup_byname(struct inode *inode, struct qstr *name, struct object_info *obj)
136{
137 struct super_block *sb = inode->i_sb;
138 struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
139 struct adfs_dir dir;
140 int ret;
141
142 ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
143 if (ret)
144 goto out;
145
146 if (ADFS_I(inode)->parent_id != dir.parent_id) {
147 adfs_error(sb, "parent directory changed under me! (%lx but got %lx)\n",
148 ADFS_I(inode)->parent_id, dir.parent_id);
149 ret = -EIO;
150 goto free_out;
151 }
152
153 obj->parent_id = inode->i_ino;
154
155 /*
156 * '.' is handled by reserved_lookup() in fs/namei.c
157 */
158 if (name->len == 2 && name->name[0] == '.' && name->name[1] == '.') {
159 /*
160 * Currently unable to fill in the rest of 'obj',
161 * but this is better than nothing. We need to
162 * ascend one level to find it's parent.
163 */
164 obj->name_len = 0;
165 obj->file_id = obj->parent_id;
166 goto free_out;
167 }
168
169 read_lock(&adfs_dir_lock);
170
171 ret = ops->setpos(&dir, 0);
172 if (ret)
173 goto unlock_out;
174
175 ret = -ENOENT;
176 while (ops->getnext(&dir, obj) == 0) {
177 if (adfs_match(name, obj)) {
178 ret = 0;
179 break;
180 }
181 }
182
183unlock_out:
184 read_unlock(&adfs_dir_lock);
185
186free_out:
187 ops->free(&dir);
188out:
189 return ret;
190}
191
192const struct file_operations adfs_dir_operations = {
193 .read = generic_read_dir,
194 .llseek = generic_file_llseek,
195 .readdir = adfs_readdir,
196 .fsync = generic_file_fsync,
197};
198
199static int
200adfs_hash(const struct dentry *parent, const struct inode *inode,
201 struct qstr *qstr)
202{
203 const unsigned int name_len = ADFS_SB(parent->d_sb)->s_namelen;
204 const unsigned char *name;
205 unsigned long hash;
206 int i;
207
208 if (qstr->len < name_len)
209 return 0;
210
211 /*
212 * Truncate the name in place, avoids
213 * having to define a compare function.
214 */
215 qstr->len = i = name_len;
216 name = qstr->name;
217 hash = init_name_hash();
218 while (i--) {
219 char c;
220
221 c = *name++;
222 if (c >= 'A' && c <= 'Z')
223 c += 'a' - 'A';
224
225 hash = partial_name_hash(c, hash);
226 }
227 qstr->hash = end_name_hash(hash);
228
229 return 0;
230}
231
232/*
233 * Compare two names, taking note of the name length
234 * requirements of the underlying filesystem.
235 */
236static int
237adfs_compare(const struct dentry *parent, const struct inode *pinode,
238 const struct dentry *dentry, const struct inode *inode,
239 unsigned int len, const char *str, const struct qstr *name)
240{
241 int i;
242
243 if (len != name->len)
244 return 1;
245
246 for (i = 0; i < name->len; i++) {
247 char a, b;
248
249 a = str[i];
250 b = name->name[i];
251
252 if (a >= 'A' && a <= 'Z')
253 a += 'a' - 'A';
254 if (b >= 'A' && b <= 'Z')
255 b += 'a' - 'A';
256
257 if (a != b)
258 return 1;
259 }
260 return 0;
261}
262
263const struct dentry_operations adfs_dentry_operations = {
264 .d_hash = adfs_hash,
265 .d_compare = adfs_compare,
266};
267
268static struct dentry *
269adfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
270{
271 struct inode *inode = NULL;
272 struct object_info obj;
273 int error;
274
275 error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj);
276 if (error == 0) {
277 error = -EACCES;
278 /*
279 * This only returns NULL if get_empty_inode
280 * fails.
281 */
282 inode = adfs_iget(dir->i_sb, &obj);
283 if (inode)
284 error = 0;
285 }
286 d_add(dentry, inode);
287 return ERR_PTR(error);
288}
289
290/*
291 * directories can handle most operations...
292 */
293const struct inode_operations adfs_dir_inode_operations = {
294 .lookup = adfs_lookup,
295 .setattr = adfs_notify_change,
296};
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/adfs/dir.c
4 *
5 * Copyright (C) 1999-2000 Russell King
6 *
7 * Common directory handling for ADFS
8 */
9#include <linux/slab.h>
10#include "adfs.h"
11
12/*
13 * For future. This should probably be per-directory.
14 */
15static DECLARE_RWSEM(adfs_dir_rwsem);
16
17int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset,
18 size_t len)
19{
20 struct super_block *sb = dir->sb;
21 unsigned int index, remain;
22
23 index = offset >> sb->s_blocksize_bits;
24 offset &= sb->s_blocksize - 1;
25 remain = sb->s_blocksize - offset;
26 if (index + (remain < len) >= dir->nr_buffers)
27 return -EINVAL;
28
29 if (remain < len) {
30 memcpy(dst, dir->bhs[index]->b_data + offset, remain);
31 dst += remain;
32 len -= remain;
33 index += 1;
34 offset = 0;
35 }
36
37 memcpy(dst, dir->bhs[index]->b_data + offset, len);
38
39 return 0;
40}
41
42int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src,
43 size_t len)
44{
45 struct super_block *sb = dir->sb;
46 unsigned int index, remain;
47
48 index = offset >> sb->s_blocksize_bits;
49 offset &= sb->s_blocksize - 1;
50 remain = sb->s_blocksize - offset;
51 if (index + (remain < len) >= dir->nr_buffers)
52 return -EINVAL;
53
54 if (remain < len) {
55 memcpy(dir->bhs[index]->b_data + offset, src, remain);
56 src += remain;
57 len -= remain;
58 index += 1;
59 offset = 0;
60 }
61
62 memcpy(dir->bhs[index]->b_data + offset, src, len);
63
64 return 0;
65}
66
67static void __adfs_dir_cleanup(struct adfs_dir *dir)
68{
69 dir->nr_buffers = 0;
70
71 if (dir->bhs != dir->bh)
72 kfree(dir->bhs);
73 dir->bhs = NULL;
74 dir->sb = NULL;
75}
76
77void adfs_dir_relse(struct adfs_dir *dir)
78{
79 unsigned int i;
80
81 for (i = 0; i < dir->nr_buffers; i++)
82 brelse(dir->bhs[i]);
83
84 __adfs_dir_cleanup(dir);
85}
86
87static void adfs_dir_forget(struct adfs_dir *dir)
88{
89 unsigned int i;
90
91 for (i = 0; i < dir->nr_buffers; i++)
92 bforget(dir->bhs[i]);
93
94 __adfs_dir_cleanup(dir);
95}
96
97int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr,
98 unsigned int size, struct adfs_dir *dir)
99{
100 struct buffer_head **bhs;
101 unsigned int i, num;
102 int block;
103
104 num = ALIGN(size, sb->s_blocksize) >> sb->s_blocksize_bits;
105 if (num > ARRAY_SIZE(dir->bh)) {
106 /* We only allow one extension */
107 if (dir->bhs != dir->bh)
108 return -EINVAL;
109
110 bhs = kcalloc(num, sizeof(*bhs), GFP_KERNEL);
111 if (!bhs)
112 return -ENOMEM;
113
114 if (dir->nr_buffers)
115 memcpy(bhs, dir->bhs, dir->nr_buffers * sizeof(*bhs));
116
117 dir->bhs = bhs;
118 }
119
120 for (i = dir->nr_buffers; i < num; i++) {
121 block = __adfs_block_map(sb, indaddr, i);
122 if (!block) {
123 adfs_error(sb, "dir %06x has a hole at offset %u",
124 indaddr, i);
125 goto error;
126 }
127
128 dir->bhs[i] = sb_bread(sb, block);
129 if (!dir->bhs[i]) {
130 adfs_error(sb,
131 "dir %06x failed read at offset %u, mapped block 0x%08x",
132 indaddr, i, block);
133 goto error;
134 }
135
136 dir->nr_buffers++;
137 }
138 return 0;
139
140error:
141 adfs_dir_relse(dir);
142
143 return -EIO;
144}
145
146static int adfs_dir_read(struct super_block *sb, u32 indaddr,
147 unsigned int size, struct adfs_dir *dir)
148{
149 dir->sb = sb;
150 dir->bhs = dir->bh;
151 dir->nr_buffers = 0;
152
153 return ADFS_SB(sb)->s_dir->read(sb, indaddr, size, dir);
154}
155
156static int adfs_dir_read_inode(struct super_block *sb, struct inode *inode,
157 struct adfs_dir *dir)
158{
159 int ret;
160
161 ret = adfs_dir_read(sb, ADFS_I(inode)->indaddr, inode->i_size, dir);
162 if (ret)
163 return ret;
164
165 if (ADFS_I(inode)->parent_id != dir->parent_id) {
166 adfs_error(sb,
167 "parent directory id changed under me! (%06x but got %06x)\n",
168 ADFS_I(inode)->parent_id, dir->parent_id);
169 adfs_dir_relse(dir);
170 ret = -EIO;
171 }
172
173 return ret;
174}
175
176static void adfs_dir_mark_dirty(struct adfs_dir *dir)
177{
178 unsigned int i;
179
180 /* Mark the buffers dirty */
181 for (i = 0; i < dir->nr_buffers; i++)
182 mark_buffer_dirty(dir->bhs[i]);
183}
184
185static int adfs_dir_sync(struct adfs_dir *dir)
186{
187 int err = 0;
188 int i;
189
190 for (i = dir->nr_buffers - 1; i >= 0; i--) {
191 struct buffer_head *bh = dir->bhs[i];
192 sync_dirty_buffer(bh);
193 if (buffer_req(bh) && !buffer_uptodate(bh))
194 err = -EIO;
195 }
196
197 return err;
198}
199
200void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj)
201{
202 unsigned int dots, i;
203
204 /*
205 * RISC OS allows the use of '/' in directory entry names, so we need
206 * to fix these up. '/' is typically used for FAT compatibility to
207 * represent '.', so do the same conversion here. In any case, '.'
208 * will never be in a RISC OS name since it is used as the pathname
209 * separator. Handle the case where we may generate a '.' or '..'
210 * name, replacing the first character with '^' (the RISC OS "parent
211 * directory" character.)
212 */
213 for (i = dots = 0; i < obj->name_len; i++)
214 if (obj->name[i] == '/') {
215 obj->name[i] = '.';
216 dots++;
217 }
218
219 if (obj->name_len <= 2 && dots == obj->name_len)
220 obj->name[0] = '^';
221
222 /*
223 * If the object is a file, and the user requested the ,xyz hex
224 * filetype suffix to the name, check the filetype and append.
225 */
226 if (!(obj->attr & ADFS_NDA_DIRECTORY) && ADFS_SB(dir->sb)->s_ftsuffix) {
227 u16 filetype = adfs_filetype(obj->loadaddr);
228
229 if (filetype != ADFS_FILETYPE_NONE) {
230 obj->name[obj->name_len++] = ',';
231 obj->name[obj->name_len++] = hex_asc_lo(filetype >> 8);
232 obj->name[obj->name_len++] = hex_asc_lo(filetype >> 4);
233 obj->name[obj->name_len++] = hex_asc_lo(filetype >> 0);
234 }
235 }
236}
237
238static int adfs_iterate(struct file *file, struct dir_context *ctx)
239{
240 struct inode *inode = file_inode(file);
241 struct super_block *sb = inode->i_sb;
242 const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
243 struct adfs_dir dir;
244 int ret;
245
246 down_read(&adfs_dir_rwsem);
247 ret = adfs_dir_read_inode(sb, inode, &dir);
248 if (ret)
249 goto unlock;
250
251 if (ctx->pos == 0) {
252 if (!dir_emit_dot(file, ctx))
253 goto unlock_relse;
254 ctx->pos = 1;
255 }
256 if (ctx->pos == 1) {
257 if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR))
258 goto unlock_relse;
259 ctx->pos = 2;
260 }
261
262 ret = ops->iterate(&dir, ctx);
263
264unlock_relse:
265 up_read(&adfs_dir_rwsem);
266 adfs_dir_relse(&dir);
267 return ret;
268
269unlock:
270 up_read(&adfs_dir_rwsem);
271 return ret;
272}
273
274int
275adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait)
276{
277 const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
278 struct adfs_dir dir;
279 int ret;
280
281 if (!IS_ENABLED(CONFIG_ADFS_FS_RW))
282 return -EINVAL;
283
284 if (!ops->update)
285 return -EINVAL;
286
287 down_write(&adfs_dir_rwsem);
288 ret = adfs_dir_read(sb, obj->parent_id, 0, &dir);
289 if (ret)
290 goto unlock;
291
292 ret = ops->update(&dir, obj);
293 if (ret)
294 goto forget;
295
296 ret = ops->commit(&dir);
297 if (ret)
298 goto forget;
299 up_write(&adfs_dir_rwsem);
300
301 adfs_dir_mark_dirty(&dir);
302
303 if (wait)
304 ret = adfs_dir_sync(&dir);
305
306 adfs_dir_relse(&dir);
307 return ret;
308
309 /*
310 * If the updated failed because the entry wasn't found, we can
311 * just release the buffers. If it was any other error, forget
312 * the dirtied buffers so they aren't written back to the media.
313 */
314forget:
315 if (ret == -ENOENT)
316 adfs_dir_relse(&dir);
317 else
318 adfs_dir_forget(&dir);
319unlock:
320 up_write(&adfs_dir_rwsem);
321
322 return ret;
323}
324
325static unsigned char adfs_tolower(unsigned char c)
326{
327 if (c >= 'A' && c <= 'Z')
328 c += 'a' - 'A';
329 return c;
330}
331
332static int __adfs_compare(const unsigned char *qstr, u32 qlen,
333 const char *str, u32 len)
334{
335 u32 i;
336
337 if (qlen != len)
338 return 1;
339
340 for (i = 0; i < qlen; i++)
341 if (adfs_tolower(qstr[i]) != adfs_tolower(str[i]))
342 return 1;
343
344 return 0;
345}
346
347static int adfs_dir_lookup_byname(struct inode *inode, const struct qstr *qstr,
348 struct object_info *obj)
349{
350 struct super_block *sb = inode->i_sb;
351 const struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
352 const unsigned char *name;
353 struct adfs_dir dir;
354 u32 name_len;
355 int ret;
356
357 down_read(&adfs_dir_rwsem);
358 ret = adfs_dir_read_inode(sb, inode, &dir);
359 if (ret)
360 goto unlock;
361
362 ret = ops->setpos(&dir, 0);
363 if (ret)
364 goto unlock_relse;
365
366 ret = -ENOENT;
367 name = qstr->name;
368 name_len = qstr->len;
369 while (ops->getnext(&dir, obj) == 0) {
370 if (!__adfs_compare(name, name_len, obj->name, obj->name_len)) {
371 ret = 0;
372 break;
373 }
374 }
375 obj->parent_id = ADFS_I(inode)->indaddr;
376
377unlock_relse:
378 up_read(&adfs_dir_rwsem);
379 adfs_dir_relse(&dir);
380 return ret;
381
382unlock:
383 up_read(&adfs_dir_rwsem);
384 return ret;
385}
386
387const struct file_operations adfs_dir_operations = {
388 .read = generic_read_dir,
389 .llseek = generic_file_llseek,
390 .iterate_shared = adfs_iterate,
391 .fsync = generic_file_fsync,
392};
393
394static int
395adfs_hash(const struct dentry *parent, struct qstr *qstr)
396{
397 const unsigned char *name;
398 unsigned long hash;
399 u32 len;
400
401 if (qstr->len > ADFS_SB(parent->d_sb)->s_namelen)
402 return -ENAMETOOLONG;
403
404 len = qstr->len;
405 name = qstr->name;
406 hash = init_name_hash(parent);
407 while (len--)
408 hash = partial_name_hash(adfs_tolower(*name++), hash);
409 qstr->hash = end_name_hash(hash);
410
411 return 0;
412}
413
414/*
415 * Compare two names, taking note of the name length
416 * requirements of the underlying filesystem.
417 */
418static int adfs_compare(const struct dentry *dentry, unsigned int len,
419 const char *str, const struct qstr *qstr)
420{
421 return __adfs_compare(qstr->name, qstr->len, str, len);
422}
423
424const struct dentry_operations adfs_dentry_operations = {
425 .d_hash = adfs_hash,
426 .d_compare = adfs_compare,
427};
428
429static struct dentry *
430adfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
431{
432 struct inode *inode = NULL;
433 struct object_info obj;
434 int error;
435
436 error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj);
437 if (error == 0) {
438 /*
439 * This only returns NULL if get_empty_inode
440 * fails.
441 */
442 inode = adfs_iget(dir->i_sb, &obj);
443 if (!inode)
444 inode = ERR_PTR(-EACCES);
445 } else if (error != -ENOENT) {
446 inode = ERR_PTR(error);
447 }
448 return d_splice_alias(inode, dentry);
449}
450
451/*
452 * directories can handle most operations...
453 */
454const struct inode_operations adfs_dir_inode_operations = {
455 .lookup = adfs_lookup,
456 .setattr = adfs_notify_change,
457};