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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/fs/ufs/ufs_dir.c | |
4 | * | |
5 | * Copyright (C) 1996 | |
6 | * Adrian Rodriguez ([email protected]) | |
7 | * Laboratory for Computer Science Research Computing Facility | |
8 | * Rutgers, The State University of New Jersey | |
9 | * | |
10 | * swab support by Francois-Rene Rideau <[email protected]> 19970406 | |
11 | * | |
12 | * 4.4BSD (FreeBSD) support added on February 1st 1998 by | |
13 | * Niels Kristian Bech Jensen <[email protected]> partially based | |
14 | * on code by Martin von Loewis <[email protected]>. | |
b71034e5 ED |
15 | * |
16 | * Migration to usage of "page cache" on May 2006 by | |
17 | * Evgeniy Dushistov <[email protected]> based on ext2 code base. | |
1da177e4 LT |
18 | */ |
19 | ||
20 | #include <linux/time.h> | |
21 | #include <linux/fs.h> | |
82b9d1d0 | 22 | #include <linux/swap.h> |
bb8c2d66 | 23 | #include <linux/iversion.h> |
1da177e4 | 24 | |
e5420598 | 25 | #include "ufs_fs.h" |
bcd6d4ec | 26 | #include "ufs.h" |
1da177e4 LT |
27 | #include "swab.h" |
28 | #include "util.h" | |
29 | ||
1da177e4 LT |
30 | /* |
31 | * NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure. | |
32 | * | |
33 | * len <= UFS_MAXNAMLEN and de != NULL are guaranteed by caller. | |
34 | */ | |
35 | static inline int ufs_match(struct super_block *sb, int len, | |
89031bc7 | 36 | const unsigned char *name, struct ufs_dir_entry *de) |
1da177e4 LT |
37 | { |
38 | if (len != ufs_get_de_namlen(sb, de)) | |
39 | return 0; | |
40 | if (!de->d_ino) | |
41 | return 0; | |
42 | return !memcmp(name, de->d_name, len); | |
43 | } | |
44 | ||
82b9d1d0 | 45 | static int ufs_commit_chunk(struct page *page, loff_t pos, unsigned len) |
1da177e4 | 46 | { |
82b9d1d0 NP |
47 | struct address_space *mapping = page->mapping; |
48 | struct inode *dir = mapping->host; | |
b71034e5 | 49 | int err = 0; |
82b9d1d0 | 50 | |
bb8c2d66 | 51 | inode_inc_iversion(dir); |
82b9d1d0 NP |
52 | block_write_end(NULL, mapping, pos, len, len, page, NULL); |
53 | if (pos+len > dir->i_size) { | |
54 | i_size_write(dir, pos+len); | |
55 | mark_inode_dirty(dir); | |
56 | } | |
b71034e5 | 57 | if (IS_DIRSYNC(dir)) |
2b69c828 | 58 | err = write_one_page(page); |
b71034e5 ED |
59 | else |
60 | unlock_page(page); | |
61 | return err; | |
62 | } | |
1da177e4 | 63 | |
b71034e5 ED |
64 | static inline void ufs_put_page(struct page *page) |
65 | { | |
66 | kunmap(page); | |
09cbfeaf | 67 | put_page(page); |
b71034e5 | 68 | } |
1da177e4 | 69 | |
89031bc7 | 70 | ino_t ufs_inode_by_name(struct inode *dir, const struct qstr *qstr) |
b71034e5 ED |
71 | { |
72 | ino_t res = 0; | |
73 | struct ufs_dir_entry *de; | |
74 | struct page *page; | |
75 | ||
08049707 | 76 | de = ufs_find_entry(dir, qstr, &page); |
b71034e5 ED |
77 | if (de) { |
78 | res = fs32_to_cpu(dir->i_sb, de->d_ino); | |
79 | ufs_put_page(page); | |
1da177e4 | 80 | } |
b71034e5 | 81 | return res; |
1da177e4 LT |
82 | } |
83 | ||
1da177e4 | 84 | |
b71034e5 ED |
85 | /* Releases the page */ |
86 | void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de, | |
70d45cdb AV |
87 | struct page *page, struct inode *inode, |
88 | bool update_times) | |
1da177e4 | 89 | { |
82b9d1d0 NP |
90 | loff_t pos = page_offset(page) + |
91 | (char *) de - (char *) page_address(page); | |
92 | unsigned len = fs16_to_cpu(dir->i_sb, de->d_reclen); | |
b71034e5 | 93 | int err; |
1da177e4 | 94 | |
b71034e5 | 95 | lock_page(page); |
f4e420dc | 96 | err = ufs_prepare_chunk(page, pos, len); |
b71034e5 | 97 | BUG_ON(err); |
82b9d1d0 | 98 | |
b71034e5 ED |
99 | de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino); |
100 | ufs_set_de_type(dir->i_sb, de, inode->i_mode); | |
82b9d1d0 NP |
101 | |
102 | err = ufs_commit_chunk(page, pos, len); | |
b71034e5 | 103 | ufs_put_page(page); |
70d45cdb | 104 | if (update_times) |
02027d42 | 105 | dir->i_mtime = dir->i_ctime = current_time(dir); |
b71034e5 ED |
106 | mark_inode_dirty(dir); |
107 | } | |
1da177e4 | 108 | |
1da177e4 | 109 | |
be5b82db | 110 | static bool ufs_check_page(struct page *page) |
b71034e5 ED |
111 | { |
112 | struct inode *dir = page->mapping->host; | |
113 | struct super_block *sb = dir->i_sb; | |
114 | char *kaddr = page_address(page); | |
115 | unsigned offs, rec_len; | |
09cbfeaf | 116 | unsigned limit = PAGE_SIZE; |
f336953b | 117 | const unsigned chunk_mask = UFS_SB(sb)->s_uspi->s_dirblksize - 1; |
b71034e5 ED |
118 | struct ufs_dir_entry *p; |
119 | char *error; | |
120 | ||
09cbfeaf KS |
121 | if ((dir->i_size >> PAGE_SHIFT) == page->index) { |
122 | limit = dir->i_size & ~PAGE_MASK; | |
f336953b | 123 | if (limit & chunk_mask) |
b71034e5 ED |
124 | goto Ebadsize; |
125 | if (!limit) | |
126 | goto out; | |
1da177e4 | 127 | } |
b71034e5 ED |
128 | for (offs = 0; offs <= limit - UFS_DIR_REC_LEN(1); offs += rec_len) { |
129 | p = (struct ufs_dir_entry *)(kaddr + offs); | |
130 | rec_len = fs16_to_cpu(sb, p->d_reclen); | |
131 | ||
132 | if (rec_len < UFS_DIR_REC_LEN(1)) | |
133 | goto Eshort; | |
134 | if (rec_len & 3) | |
135 | goto Ealign; | |
136 | if (rec_len < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, p))) | |
137 | goto Enamelen; | |
f336953b | 138 | if (((offs + rec_len - 1) ^ offs) & ~chunk_mask) |
b71034e5 ED |
139 | goto Espan; |
140 | if (fs32_to_cpu(sb, p->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg * | |
141 | UFS_SB(sb)->s_uspi->s_ncg)) | |
142 | goto Einumber; | |
143 | } | |
144 | if (offs != limit) | |
145 | goto Eend; | |
146 | out: | |
147 | SetPageChecked(page); | |
be5b82db | 148 | return true; |
b71034e5 ED |
149 | |
150 | /* Too bad, we had an error */ | |
151 | ||
152 | Ebadsize: | |
153 | ufs_error(sb, "ufs_check_page", | |
154 | "size of directory #%lu is not a multiple of chunk size", | |
155 | dir->i_ino | |
156 | ); | |
157 | goto fail; | |
158 | Eshort: | |
159 | error = "rec_len is smaller than minimal"; | |
160 | goto bad_entry; | |
161 | Ealign: | |
162 | error = "unaligned directory entry"; | |
163 | goto bad_entry; | |
164 | Enamelen: | |
165 | error = "rec_len is too small for name_len"; | |
166 | goto bad_entry; | |
167 | Espan: | |
168 | error = "directory entry across blocks"; | |
169 | goto bad_entry; | |
170 | Einumber: | |
171 | error = "inode out of bounds"; | |
172 | bad_entry: | |
173 | ufs_error (sb, "ufs_check_page", "bad entry in directory #%lu: %s - " | |
174 | "offset=%lu, rec_len=%d, name_len=%d", | |
09cbfeaf | 175 | dir->i_ino, error, (page->index<<PAGE_SHIFT)+offs, |
b71034e5 ED |
176 | rec_len, ufs_get_de_namlen(sb, p)); |
177 | goto fail; | |
178 | Eend: | |
179 | p = (struct ufs_dir_entry *)(kaddr + offs); | |
9746077a | 180 | ufs_error(sb, __func__, |
b71034e5 ED |
181 | "entry in directory #%lu spans the page boundary" |
182 | "offset=%lu", | |
09cbfeaf | 183 | dir->i_ino, (page->index<<PAGE_SHIFT)+offs); |
b71034e5 | 184 | fail: |
b71034e5 | 185 | SetPageError(page); |
be5b82db | 186 | return false; |
b71034e5 | 187 | } |
1da177e4 | 188 | |
b71034e5 ED |
189 | static struct page *ufs_get_page(struct inode *dir, unsigned long n) |
190 | { | |
191 | struct address_space *mapping = dir->i_mapping; | |
6fe6900e | 192 | struct page *page = read_mapping_page(mapping, n, NULL); |
b71034e5 | 193 | if (!IS_ERR(page)) { |
b71034e5 | 194 | kmap(page); |
be5b82db AV |
195 | if (unlikely(!PageChecked(page))) { |
196 | if (PageError(page) || !ufs_check_page(page)) | |
197 | goto fail; | |
198 | } | |
1da177e4 | 199 | } |
b71034e5 | 200 | return page; |
1da177e4 | 201 | |
b71034e5 ED |
202 | fail: |
203 | ufs_put_page(page); | |
204 | return ERR_PTR(-EIO); | |
1da177e4 LT |
205 | } |
206 | ||
b71034e5 ED |
207 | /* |
208 | * Return the offset into page `page_nr' of the last valid | |
209 | * byte in that page, plus one. | |
210 | */ | |
211 | static unsigned | |
212 | ufs_last_byte(struct inode *inode, unsigned long page_nr) | |
1da177e4 | 213 | { |
b71034e5 ED |
214 | unsigned last_byte = inode->i_size; |
215 | ||
09cbfeaf KS |
216 | last_byte -= page_nr << PAGE_SHIFT; |
217 | if (last_byte > PAGE_SIZE) | |
218 | last_byte = PAGE_SIZE; | |
b71034e5 | 219 | return last_byte; |
1da177e4 LT |
220 | } |
221 | ||
b71034e5 ED |
222 | static inline struct ufs_dir_entry * |
223 | ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p) | |
1da177e4 | 224 | { |
b71034e5 ED |
225 | return (struct ufs_dir_entry *)((char *)p + |
226 | fs16_to_cpu(sb, p->d_reclen)); | |
1da177e4 | 227 | } |
b71034e5 ED |
228 | |
229 | struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p) | |
1da177e4 | 230 | { |
b71034e5 ED |
231 | struct page *page = ufs_get_page(dir, 0); |
232 | struct ufs_dir_entry *de = NULL; | |
1da177e4 | 233 | |
b71034e5 ED |
234 | if (!IS_ERR(page)) { |
235 | de = ufs_next_entry(dir->i_sb, | |
236 | (struct ufs_dir_entry *)page_address(page)); | |
237 | *p = page; | |
1da177e4 | 238 | } |
b71034e5 | 239 | return de; |
1da177e4 LT |
240 | } |
241 | ||
b71034e5 ED |
242 | /* |
243 | * ufs_find_entry() | |
244 | * | |
245 | * finds an entry in the specified directory with the wanted name. It | |
246 | * returns the page in which the entry was found, and the entry itself | |
247 | * (as a parameter - res_dir). Page is returned mapped and unlocked. | |
248 | * Entry is guaranteed to be valid. | |
249 | */ | |
89031bc7 | 250 | struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr, |
b71034e5 | 251 | struct page **res_page) |
1da177e4 | 252 | { |
b71034e5 | 253 | struct super_block *sb = dir->i_sb; |
89031bc7 | 254 | const unsigned char *name = qstr->name; |
08049707 | 255 | int namelen = qstr->len; |
b71034e5 ED |
256 | unsigned reclen = UFS_DIR_REC_LEN(namelen); |
257 | unsigned long start, n; | |
5d754ced | 258 | unsigned long npages = dir_pages(dir); |
b71034e5 | 259 | struct page *page = NULL; |
dd187a26 | 260 | struct ufs_inode_info *ui = UFS_I(dir); |
b71034e5 ED |
261 | struct ufs_dir_entry *de; |
262 | ||
abf5d15f | 263 | UFSD("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen); |
b71034e5 ED |
264 | |
265 | if (npages == 0 || namelen > UFS_MAXNAMLEN) | |
266 | goto out; | |
267 | ||
268 | /* OFFSET_CACHE */ | |
269 | *res_page = NULL; | |
270 | ||
dd187a26 ED |
271 | start = ui->i_dir_start_lookup; |
272 | ||
b71034e5 ED |
273 | if (start >= npages) |
274 | start = 0; | |
275 | n = start; | |
276 | do { | |
277 | char *kaddr; | |
278 | page = ufs_get_page(dir, n); | |
279 | if (!IS_ERR(page)) { | |
280 | kaddr = page_address(page); | |
281 | de = (struct ufs_dir_entry *) kaddr; | |
282 | kaddr += ufs_last_byte(dir, n) - reclen; | |
283 | while ((char *) de <= kaddr) { | |
b71034e5 ED |
284 | if (ufs_match(sb, namelen, name, de)) |
285 | goto found; | |
286 | de = ufs_next_entry(sb, de); | |
287 | } | |
288 | ufs_put_page(page); | |
289 | } | |
290 | if (++n >= npages) | |
291 | n = 0; | |
292 | } while (n != start); | |
293 | out: | |
294 | return NULL; | |
295 | ||
296 | found: | |
297 | *res_page = page; | |
dd187a26 | 298 | ui->i_dir_start_lookup = n; |
b71034e5 | 299 | return de; |
1da177e4 LT |
300 | } |
301 | ||
302 | /* | |
b71034e5 | 303 | * Parent is locked. |
1da177e4 LT |
304 | */ |
305 | int ufs_add_link(struct dentry *dentry, struct inode *inode) | |
306 | { | |
2b0143b5 | 307 | struct inode *dir = d_inode(dentry->d_parent); |
89031bc7 | 308 | const unsigned char *name = dentry->d_name.name; |
1da177e4 | 309 | int namelen = dentry->d_name.len; |
b71034e5 ED |
310 | struct super_block *sb = dir->i_sb; |
311 | unsigned reclen = UFS_DIR_REC_LEN(namelen); | |
f336953b | 312 | const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize; |
b71034e5 ED |
313 | unsigned short rec_len, name_len; |
314 | struct page *page = NULL; | |
315 | struct ufs_dir_entry *de; | |
5d754ced | 316 | unsigned long npages = dir_pages(dir); |
b71034e5 ED |
317 | unsigned long n; |
318 | char *kaddr; | |
82b9d1d0 | 319 | loff_t pos; |
1da177e4 LT |
320 | int err; |
321 | ||
abf5d15f | 322 | UFSD("ENTER, name %s, namelen %u\n", name, namelen); |
b71034e5 ED |
323 | |
324 | /* | |
325 | * We take care of directory expansion in the same loop. | |
326 | * This code plays outside i_size, so it locks the page | |
327 | * to protect that region. | |
328 | */ | |
329 | for (n = 0; n <= npages; n++) { | |
330 | char *dir_end; | |
331 | ||
332 | page = ufs_get_page(dir, n); | |
333 | err = PTR_ERR(page); | |
334 | if (IS_ERR(page)) | |
335 | goto out; | |
336 | lock_page(page); | |
337 | kaddr = page_address(page); | |
338 | dir_end = kaddr + ufs_last_byte(dir, n); | |
339 | de = (struct ufs_dir_entry *)kaddr; | |
09cbfeaf | 340 | kaddr += PAGE_SIZE - reclen; |
b71034e5 ED |
341 | while ((char *)de <= kaddr) { |
342 | if ((char *)de == dir_end) { | |
343 | /* We hit i_size */ | |
344 | name_len = 0; | |
f336953b ED |
345 | rec_len = chunk_size; |
346 | de->d_reclen = cpu_to_fs16(sb, chunk_size); | |
b71034e5 ED |
347 | de->d_ino = 0; |
348 | goto got_it; | |
1da177e4 | 349 | } |
b71034e5 | 350 | if (de->d_reclen == 0) { |
9746077a | 351 | ufs_error(dir->i_sb, __func__, |
b71034e5 ED |
352 | "zero-length directory entry"); |
353 | err = -EIO; | |
354 | goto out_unlock; | |
355 | } | |
356 | err = -EEXIST; | |
357 | if (ufs_match(sb, namelen, name, de)) | |
358 | goto out_unlock; | |
359 | name_len = UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)); | |
360 | rec_len = fs16_to_cpu(sb, de->d_reclen); | |
361 | if (!de->d_ino && rec_len >= reclen) | |
362 | goto got_it; | |
363 | if (rec_len >= name_len + reclen) | |
364 | goto got_it; | |
365 | de = (struct ufs_dir_entry *) ((char *) de + rec_len); | |
1da177e4 | 366 | } |
b71034e5 ED |
367 | unlock_page(page); |
368 | ufs_put_page(page); | |
1da177e4 | 369 | } |
b71034e5 ED |
370 | BUG(); |
371 | return -EINVAL; | |
372 | ||
373 | got_it: | |
82b9d1d0 NP |
374 | pos = page_offset(page) + |
375 | (char*)de - (char*)page_address(page); | |
f4e420dc | 376 | err = ufs_prepare_chunk(page, pos, rec_len); |
b71034e5 ED |
377 | if (err) |
378 | goto out_unlock; | |
1da177e4 | 379 | if (de->d_ino) { |
b71034e5 ED |
380 | struct ufs_dir_entry *de1 = |
381 | (struct ufs_dir_entry *) ((char *) de + name_len); | |
382 | de1->d_reclen = cpu_to_fs16(sb, rec_len - name_len); | |
383 | de->d_reclen = cpu_to_fs16(sb, name_len); | |
384 | ||
1da177e4 LT |
385 | de = de1; |
386 | } | |
b71034e5 | 387 | |
1da177e4 | 388 | ufs_set_de_namlen(sb, de, namelen); |
b71034e5 | 389 | memcpy(de->d_name, name, namelen + 1); |
1da177e4 LT |
390 | de->d_ino = cpu_to_fs32(sb, inode->i_ino); |
391 | ufs_set_de_type(sb, de, inode->i_mode); | |
b71034e5 | 392 | |
82b9d1d0 | 393 | err = ufs_commit_chunk(page, pos, rec_len); |
02027d42 | 394 | dir->i_mtime = dir->i_ctime = current_time(dir); |
b71034e5 | 395 | |
1da177e4 | 396 | mark_inode_dirty(dir); |
b71034e5 ED |
397 | /* OFFSET_CACHE */ |
398 | out_put: | |
399 | ufs_put_page(page); | |
400 | out: | |
401 | return err; | |
402 | out_unlock: | |
403 | unlock_page(page); | |
404 | goto out_put; | |
405 | } | |
406 | ||
407 | static inline unsigned | |
408 | ufs_validate_entry(struct super_block *sb, char *base, | |
409 | unsigned offset, unsigned mask) | |
410 | { | |
411 | struct ufs_dir_entry *de = (struct ufs_dir_entry*)(base + offset); | |
412 | struct ufs_dir_entry *p = (struct ufs_dir_entry*)(base + (offset&mask)); | |
e0d508f1 | 413 | while ((char*)p < (char*)de) |
b71034e5 | 414 | p = ufs_next_entry(sb, p); |
b71034e5 ED |
415 | return (char *)p - base; |
416 | } | |
1da177e4 | 417 | |
b71034e5 ED |
418 | |
419 | /* | |
420 | * This is blatantly stolen from ext2fs | |
421 | */ | |
422 | static int | |
80886298 | 423 | ufs_readdir(struct file *file, struct dir_context *ctx) |
b71034e5 | 424 | { |
80886298 AV |
425 | loff_t pos = ctx->pos; |
426 | struct inode *inode = file_inode(file); | |
b71034e5 | 427 | struct super_block *sb = inode->i_sb; |
09cbfeaf KS |
428 | unsigned int offset = pos & ~PAGE_MASK; |
429 | unsigned long n = pos >> PAGE_SHIFT; | |
5d754ced | 430 | unsigned long npages = dir_pages(inode); |
f336953b | 431 | unsigned chunk_mask = ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); |
c472c07b | 432 | bool need_revalidate = !inode_eq_iversion(inode, file->f_version); |
b71034e5 ED |
433 | unsigned flags = UFS_SB(sb)->s_flags; |
434 | ||
abf5d15f | 435 | UFSD("BEGIN\n"); |
b71034e5 ED |
436 | |
437 | if (pos > inode->i_size - UFS_DIR_REC_LEN(1)) | |
438 | return 0; | |
439 | ||
440 | for ( ; n < npages; n++, offset = 0) { | |
441 | char *kaddr, *limit; | |
442 | struct ufs_dir_entry *de; | |
443 | ||
444 | struct page *page = ufs_get_page(inode, n); | |
445 | ||
446 | if (IS_ERR(page)) { | |
9746077a | 447 | ufs_error(sb, __func__, |
b71034e5 ED |
448 | "bad page in #%lu", |
449 | inode->i_ino); | |
09cbfeaf | 450 | ctx->pos += PAGE_SIZE - offset; |
b71034e5 ED |
451 | return -EIO; |
452 | } | |
453 | kaddr = page_address(page); | |
454 | if (unlikely(need_revalidate)) { | |
455 | if (offset) { | |
456 | offset = ufs_validate_entry(sb, kaddr, offset, chunk_mask); | |
09cbfeaf | 457 | ctx->pos = (n<<PAGE_SHIFT) + offset; |
b71034e5 | 458 | } |
bb8c2d66 JL |
459 | file->f_version = inode_query_iversion(inode); |
460 | need_revalidate = false; | |
b71034e5 ED |
461 | } |
462 | de = (struct ufs_dir_entry *)(kaddr+offset); | |
463 | limit = kaddr + ufs_last_byte(inode, n) - UFS_DIR_REC_LEN(1); | |
464 | for ( ;(char*)de <= limit; de = ufs_next_entry(sb, de)) { | |
b71034e5 | 465 | if (de->d_ino) { |
b71034e5 ED |
466 | unsigned char d_type = DT_UNKNOWN; |
467 | ||
abf5d15f ED |
468 | UFSD("filldir(%s,%u)\n", de->d_name, |
469 | fs32_to_cpu(sb, de->d_ino)); | |
470 | UFSD("namlen %u\n", ufs_get_de_namlen(sb, de)); | |
b71034e5 ED |
471 | |
472 | if ((flags & UFS_DE_MASK) == UFS_DE_44BSD) | |
473 | d_type = de->d_u.d_44.d_type; | |
474 | ||
80886298 | 475 | if (!dir_emit(ctx, de->d_name, |
b71034e5 | 476 | ufs_get_de_namlen(sb, de), |
80886298 AV |
477 | fs32_to_cpu(sb, de->d_ino), |
478 | d_type)) { | |
b71034e5 ED |
479 | ufs_put_page(page); |
480 | return 0; | |
481 | } | |
482 | } | |
80886298 | 483 | ctx->pos += fs16_to_cpu(sb, de->d_reclen); |
b71034e5 ED |
484 | } |
485 | ufs_put_page(page); | |
486 | } | |
1da177e4 LT |
487 | return 0; |
488 | } | |
489 | ||
b71034e5 | 490 | |
1da177e4 LT |
491 | /* |
492 | * ufs_delete_entry deletes a directory entry by merging it with the | |
493 | * previous entry. | |
494 | */ | |
b71034e5 ED |
495 | int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir, |
496 | struct page * page) | |
1da177e4 | 497 | { |
b71034e5 | 498 | struct super_block *sb = inode->i_sb; |
b71034e5 | 499 | char *kaddr = page_address(page); |
f336953b | 500 | unsigned from = ((char*)dir - kaddr) & ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); |
b71034e5 | 501 | unsigned to = ((char*)dir - kaddr) + fs16_to_cpu(sb, dir->d_reclen); |
82b9d1d0 | 502 | loff_t pos; |
b71034e5 ED |
503 | struct ufs_dir_entry *pde = NULL; |
504 | struct ufs_dir_entry *de = (struct ufs_dir_entry *) (kaddr + from); | |
505 | int err; | |
1da177e4 | 506 | |
abf5d15f | 507 | UFSD("ENTER\n"); |
1da177e4 | 508 | |
abf5d15f | 509 | UFSD("ino %u, reclen %u, namlen %u, name %s\n", |
b71034e5 ED |
510 | fs32_to_cpu(sb, de->d_ino), |
511 | fs16_to_cpu(sb, de->d_reclen), | |
abf5d15f | 512 | ufs_get_de_namlen(sb, de), de->d_name); |
b71034e5 ED |
513 | |
514 | while ((char*)de < (char*)dir) { | |
515 | if (de->d_reclen == 0) { | |
9746077a | 516 | ufs_error(inode->i_sb, __func__, |
b71034e5 ED |
517 | "zero-length directory entry"); |
518 | err = -EIO; | |
519 | goto out; | |
1da177e4 | 520 | } |
b71034e5 ED |
521 | pde = de; |
522 | de = ufs_next_entry(sb, de); | |
1da177e4 | 523 | } |
b71034e5 ED |
524 | if (pde) |
525 | from = (char*)pde - (char*)page_address(page); | |
82b9d1d0 NP |
526 | |
527 | pos = page_offset(page) + from; | |
b71034e5 | 528 | lock_page(page); |
f4e420dc | 529 | err = ufs_prepare_chunk(page, pos, to - from); |
b71034e5 ED |
530 | BUG_ON(err); |
531 | if (pde) | |
82b9d1d0 | 532 | pde->d_reclen = cpu_to_fs16(sb, to - from); |
b71034e5 | 533 | dir->d_ino = 0; |
82b9d1d0 | 534 | err = ufs_commit_chunk(page, pos, to - from); |
02027d42 | 535 | inode->i_ctime = inode->i_mtime = current_time(inode); |
b71034e5 ED |
536 | mark_inode_dirty(inode); |
537 | out: | |
538 | ufs_put_page(page); | |
abf5d15f | 539 | UFSD("EXIT\n"); |
b71034e5 | 540 | return err; |
1da177e4 LT |
541 | } |
542 | ||
543 | int ufs_make_empty(struct inode * inode, struct inode *dir) | |
544 | { | |
545 | struct super_block * sb = dir->i_sb; | |
b71034e5 ED |
546 | struct address_space *mapping = inode->i_mapping; |
547 | struct page *page = grab_cache_page(mapping, 0); | |
f336953b | 548 | const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize; |
1da177e4 | 549 | struct ufs_dir_entry * de; |
b71034e5 | 550 | char *base; |
1da177e4 LT |
551 | int err; |
552 | ||
b71034e5 ED |
553 | if (!page) |
554 | return -ENOMEM; | |
82b9d1d0 | 555 | |
f4e420dc | 556 | err = ufs_prepare_chunk(page, 0, chunk_size); |
b71034e5 ED |
557 | if (err) { |
558 | unlock_page(page); | |
559 | goto fail; | |
560 | } | |
561 | ||
82b9d1d0 | 562 | kmap(page); |
b71034e5 | 563 | base = (char*)page_address(page); |
09cbfeaf | 564 | memset(base, 0, PAGE_SIZE); |
b71034e5 ED |
565 | |
566 | de = (struct ufs_dir_entry *) base; | |
1da177e4 | 567 | |
1da177e4 LT |
568 | de->d_ino = cpu_to_fs32(sb, inode->i_ino); |
569 | ufs_set_de_type(sb, de, inode->i_mode); | |
570 | ufs_set_de_namlen(sb, de, 1); | |
571 | de->d_reclen = cpu_to_fs16(sb, UFS_DIR_REC_LEN(1)); | |
572 | strcpy (de->d_name, "."); | |
573 | de = (struct ufs_dir_entry *) | |
574 | ((char *)de + fs16_to_cpu(sb, de->d_reclen)); | |
575 | de->d_ino = cpu_to_fs32(sb, dir->i_ino); | |
576 | ufs_set_de_type(sb, de, dir->i_mode); | |
f336953b | 577 | de->d_reclen = cpu_to_fs16(sb, chunk_size - UFS_DIR_REC_LEN(1)); |
1da177e4 LT |
578 | ufs_set_de_namlen(sb, de, 2); |
579 | strcpy (de->d_name, ".."); | |
82b9d1d0 | 580 | kunmap(page); |
b71034e5 | 581 | |
f336953b | 582 | err = ufs_commit_chunk(page, 0, chunk_size); |
b71034e5 | 583 | fail: |
09cbfeaf | 584 | put_page(page); |
b71034e5 | 585 | return err; |
1da177e4 LT |
586 | } |
587 | ||
588 | /* | |
589 | * routine to check that the specified directory is empty (for rmdir) | |
590 | */ | |
b71034e5 | 591 | int ufs_empty_dir(struct inode * inode) |
1da177e4 | 592 | { |
b71034e5 ED |
593 | struct super_block *sb = inode->i_sb; |
594 | struct page *page = NULL; | |
5d754ced | 595 | unsigned long i, npages = dir_pages(inode); |
b71034e5 ED |
596 | |
597 | for (i = 0; i < npages; i++) { | |
598 | char *kaddr; | |
599 | struct ufs_dir_entry *de; | |
600 | page = ufs_get_page(inode, i); | |
601 | ||
602 | if (IS_ERR(page)) | |
603 | continue; | |
604 | ||
605 | kaddr = page_address(page); | |
606 | de = (struct ufs_dir_entry *)kaddr; | |
607 | kaddr += ufs_last_byte(inode, i) - UFS_DIR_REC_LEN(1); | |
608 | ||
609 | while ((char *)de <= kaddr) { | |
610 | if (de->d_reclen == 0) { | |
9746077a | 611 | ufs_error(inode->i_sb, __func__, |
b71034e5 ED |
612 | "zero-length directory entry: " |
613 | "kaddr=%p, de=%p\n", kaddr, de); | |
614 | goto not_empty; | |
1da177e4 | 615 | } |
b71034e5 ED |
616 | if (de->d_ino) { |
617 | u16 namelen=ufs_get_de_namlen(sb, de); | |
618 | /* check for . and .. */ | |
619 | if (de->d_name[0] != '.') | |
620 | goto not_empty; | |
621 | if (namelen > 2) | |
622 | goto not_empty; | |
623 | if (namelen < 2) { | |
624 | if (inode->i_ino != | |
625 | fs32_to_cpu(sb, de->d_ino)) | |
626 | goto not_empty; | |
627 | } else if (de->d_name[1] != '.') | |
628 | goto not_empty; | |
629 | } | |
630 | de = ufs_next_entry(sb, de); | |
1da177e4 | 631 | } |
b71034e5 | 632 | ufs_put_page(page); |
1da177e4 | 633 | } |
1da177e4 | 634 | return 1; |
b71034e5 ED |
635 | |
636 | not_empty: | |
637 | ufs_put_page(page); | |
638 | return 0; | |
1da177e4 LT |
639 | } |
640 | ||
4b6f5d20 | 641 | const struct file_operations ufs_dir_operations = { |
1da177e4 | 642 | .read = generic_read_dir, |
3b0a3c1a | 643 | .iterate_shared = ufs_readdir, |
1b061d92 | 644 | .fsync = generic_file_fsync, |
3222a3e5 | 645 | .llseek = generic_file_llseek, |
1da177e4 | 646 | }; |