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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 *file, struct dir_context *ctx)
21{
22 struct inode *inode = file_inode(file);
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 (ctx->pos >> 32)
30 return 0;
31
32 ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
33 if (ret)
34 return ret;
35
36 if (ctx->pos == 0) {
37 if (!dir_emit_dot(file, ctx))
38 goto free_out;
39 ctx->pos = 1;
40 }
41 if (ctx->pos == 1) {
42 if (!dir_emit(ctx, "..", 2, dir.parent_id, DT_DIR))
43 goto free_out;
44 ctx->pos = 2;
45 }
46
47 read_lock(&adfs_dir_lock);
48
49 ret = ops->setpos(&dir, ctx->pos - 2);
50 if (ret)
51 goto unlock_out;
52 while (ops->getnext(&dir, &obj) == 0) {
53 if (!dir_emit(ctx, obj.name, obj.name_len,
54 obj.file_id, DT_UNKNOWN))
55 break;
56 ctx->pos++;
57 }
58
59unlock_out:
60 read_unlock(&adfs_dir_lock);
61
62free_out:
63 ops->free(&dir);
64 return ret;
65}
66
67int
68adfs_dir_update(struct super_block *sb, struct object_info *obj, int wait)
69{
70 int ret = -EINVAL;
71#ifdef CONFIG_ADFS_FS_RW
72 struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
73 struct adfs_dir dir;
74
75 printk(KERN_INFO "adfs_dir_update: object %06X in dir %06X\n",
76 obj->file_id, obj->parent_id);
77
78 if (!ops->update) {
79 ret = -EINVAL;
80 goto out;
81 }
82
83 ret = ops->read(sb, obj->parent_id, 0, &dir);
84 if (ret)
85 goto out;
86
87 write_lock(&adfs_dir_lock);
88 ret = ops->update(&dir, obj);
89 write_unlock(&adfs_dir_lock);
90
91 if (wait) {
92 int err = ops->sync(&dir);
93 if (!ret)
94 ret = err;
95 }
96
97 ops->free(&dir);
98out:
99#endif
100 return ret;
101}
102
103static int
104adfs_match(struct qstr *name, struct object_info *obj)
105{
106 int i;
107
108 if (name->len != obj->name_len)
109 return 0;
110
111 for (i = 0; i < name->len; i++) {
112 char c1, c2;
113
114 c1 = name->name[i];
115 c2 = obj->name[i];
116
117 if (c1 >= 'A' && c1 <= 'Z')
118 c1 += 'a' - 'A';
119 if (c2 >= 'A' && c2 <= 'Z')
120 c2 += 'a' - 'A';
121
122 if (c1 != c2)
123 return 0;
124 }
125 return 1;
126}
127
128static int
129adfs_dir_lookup_byname(struct inode *inode, struct qstr *name, struct object_info *obj)
130{
131 struct super_block *sb = inode->i_sb;
132 struct adfs_dir_ops *ops = ADFS_SB(sb)->s_dir;
133 struct adfs_dir dir;
134 int ret;
135
136 ret = ops->read(sb, inode->i_ino, inode->i_size, &dir);
137 if (ret)
138 goto out;
139
140 if (ADFS_I(inode)->parent_id != dir.parent_id) {
141 adfs_error(sb, "parent directory changed under me! (%lx but got %lx)\n",
142 ADFS_I(inode)->parent_id, dir.parent_id);
143 ret = -EIO;
144 goto free_out;
145 }
146
147 obj->parent_id = inode->i_ino;
148
149 /*
150 * '.' is handled by reserved_lookup() in fs/namei.c
151 */
152 if (name->len == 2 && name->name[0] == '.' && name->name[1] == '.') {
153 /*
154 * Currently unable to fill in the rest of 'obj',
155 * but this is better than nothing. We need to
156 * ascend one level to find it's parent.
157 */
158 obj->name_len = 0;
159 obj->file_id = obj->parent_id;
160 goto free_out;
161 }
162
163 read_lock(&adfs_dir_lock);
164
165 ret = ops->setpos(&dir, 0);
166 if (ret)
167 goto unlock_out;
168
169 ret = -ENOENT;
170 while (ops->getnext(&dir, obj) == 0) {
171 if (adfs_match(name, obj)) {
172 ret = 0;
173 break;
174 }
175 }
176
177unlock_out:
178 read_unlock(&adfs_dir_lock);
179
180free_out:
181 ops->free(&dir);
182out:
183 return ret;
184}
185
186const struct file_operations adfs_dir_operations = {
187 .read = generic_read_dir,
188 .llseek = generic_file_llseek,
189 .iterate = adfs_readdir,
190 .fsync = generic_file_fsync,
191};
192
193static int
194adfs_hash(const struct dentry *parent, struct qstr *qstr)
195{
196 const unsigned int name_len = ADFS_SB(parent->d_sb)->s_namelen;
197 const unsigned char *name;
198 unsigned long hash;
199 int i;
200
201 if (qstr->len < name_len)
202 return 0;
203
204 /*
205 * Truncate the name in place, avoids
206 * having to define a compare function.
207 */
208 qstr->len = i = name_len;
209 name = qstr->name;
210 hash = init_name_hash();
211 while (i--) {
212 char c;
213
214 c = *name++;
215 if (c >= 'A' && c <= 'Z')
216 c += 'a' - 'A';
217
218 hash = partial_name_hash(c, hash);
219 }
220 qstr->hash = end_name_hash(hash);
221
222 return 0;
223}
224
225/*
226 * Compare two names, taking note of the name length
227 * requirements of the underlying filesystem.
228 */
229static int
230adfs_compare(const struct dentry *parent, const struct dentry *dentry,
231 unsigned int len, const char *str, const struct qstr *name)
232{
233 int i;
234
235 if (len != name->len)
236 return 1;
237
238 for (i = 0; i < name->len; i++) {
239 char a, b;
240
241 a = str[i];
242 b = name->name[i];
243
244 if (a >= 'A' && a <= 'Z')
245 a += 'a' - 'A';
246 if (b >= 'A' && b <= 'Z')
247 b += 'a' - 'A';
248
249 if (a != b)
250 return 1;
251 }
252 return 0;
253}
254
255const struct dentry_operations adfs_dentry_operations = {
256 .d_hash = adfs_hash,
257 .d_compare = adfs_compare,
258};
259
260static struct dentry *
261adfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
262{
263 struct inode *inode = NULL;
264 struct object_info obj;
265 int error;
266
267 error = adfs_dir_lookup_byname(dir, &dentry->d_name, &obj);
268 if (error == 0) {
269 error = -EACCES;
270 /*
271 * This only returns NULL if get_empty_inode
272 * fails.
273 */
274 inode = adfs_iget(dir->i_sb, &obj);
275 if (inode)
276 error = 0;
277 }
278 d_add(dentry, inode);
279 return ERR_PTR(error);
280}
281
282/*
283 * directories can handle most operations...
284 */
285const struct inode_operations adfs_dir_inode_operations = {
286 .lookup = adfs_lookup,
287 .setattr = adfs_notify_change,
288};
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};