1 /*
2 * linux/fs/ufs/truncate.c
3 *
4 * Copyright (C) 1998
5 * Daniel Pirkl <daniel.pirkl@email.cz>
6 * Charles University, Faculty of Mathematics and Physics
7 *
8 * from
9 *
10 * linux/fs/ext2/truncate.c
11 *
12 * Copyright (C) 1992, 1993, 1994, 1995
13 * Remy Card (card@masi.ibp.fr)
14 * Laboratoire MASI - Institut Blaise Pascal
15 * Universite Pierre et Marie Curie (Paris VI)
16 *
17 * from
18 *
19 * linux/fs/minix/truncate.c
20 *
21 * Copyright (C) 1991, 1992 Linus Torvalds
22 *
23 * Big-endian to little-endian byte-swapping/bitmaps by
24 * David S. Miller (davem@caip.rutgers.edu), 1995
25 */
26
27 /*
28 * Real random numbers for secure rm added 94/02/18
29 * Idea from Pierre del Perugia <delperug@gla.ecoledoc.ibp.fr>
30 */
31
32 /*
33 * Adoptation to use page cache and UFS2 write support by
34 * Evgeniy Dushistov <dushistov@mail.ru>, 2006-2007
35 */
36
37 #include <linux/errno.h>
38 #include <linux/fs.h>
39 #include <linux/fcntl.h>
40 #include <linux/time.h>
41 #include <linux/stat.h>
42 #include <linux/string.h>
43 #include <linux/buffer_head.h>
44 #include <linux/blkdev.h>
45 #include <linux/sched.h>
46
47 #include "ufs_fs.h"
48 #include "ufs.h"
49 #include "swab.h"
50 #include "util.h"
51
52 /*
53 * Secure deletion currently doesn't work. It interacts very badly
54 * with buffers shared with memory mappings, and for that reason
55 * can't be done in the truncate() routines. It should instead be
56 * done separately in "release()" before calling the truncate routines
57 * that will release the actual file blocks.
58 *
59 * Linus
60 */
61
62 #define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift)
63 #define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift)
64
65
ufs_trunc_direct(struct inode * inode)66 static int ufs_trunc_direct(struct inode *inode)
67 {
68 struct ufs_inode_info *ufsi = UFS_I(inode);
69 struct super_block * sb;
70 struct ufs_sb_private_info * uspi;
71 void *p;
72 u64 frag1, frag2, frag3, frag4, block1, block2;
73 unsigned frag_to_free, free_count;
74 unsigned i, tmp;
75 int retry;
76
77 UFSD("ENTER: ino %lu\n", inode->i_ino);
78
79 sb = inode->i_sb;
80 uspi = UFS_SB(sb)->s_uspi;
81
82 frag_to_free = 0;
83 free_count = 0;
84 retry = 0;
85
86 frag1 = DIRECT_FRAGMENT;
87 frag4 = min_t(u32, UFS_NDIR_FRAGMENT, ufsi->i_lastfrag);
88 frag2 = ((frag1 & uspi->s_fpbmask) ? ((frag1 | uspi->s_fpbmask) + 1) : frag1);
89 frag3 = frag4 & ~uspi->s_fpbmask;
90 block1 = block2 = 0;
91 if (frag2 > frag3) {
92 frag2 = frag4;
93 frag3 = frag4 = 0;
94 } else if (frag2 < frag3) {
95 block1 = ufs_fragstoblks (frag2);
96 block2 = ufs_fragstoblks (frag3);
97 }
98
99 UFSD("ino %lu, frag1 %llu, frag2 %llu, block1 %llu, block2 %llu,"
100 " frag3 %llu, frag4 %llu\n", inode->i_ino,
101 (unsigned long long)frag1, (unsigned long long)frag2,
102 (unsigned long long)block1, (unsigned long long)block2,
103 (unsigned long long)frag3, (unsigned long long)frag4);
104
105 if (frag1 >= frag2)
106 goto next1;
107
108 /*
109 * Free first free fragments
110 */
111 p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag1));
112 tmp = ufs_data_ptr_to_cpu(sb, p);
113 if (!tmp )
114 ufs_panic (sb, "ufs_trunc_direct", "internal error");
115 frag2 -= frag1;
116 frag1 = ufs_fragnum (frag1);
117
118 ufs_free_fragments(inode, tmp + frag1, frag2);
119 mark_inode_dirty(inode);
120 frag_to_free = tmp + frag1;
121
122 next1:
123 /*
124 * Free whole blocks
125 */
126 for (i = block1 ; i < block2; i++) {
127 p = ufs_get_direct_data_ptr(uspi, ufsi, i);
128 tmp = ufs_data_ptr_to_cpu(sb, p);
129 if (!tmp)
130 continue;
131 ufs_data_ptr_clear(uspi, p);
132
133 if (free_count == 0) {
134 frag_to_free = tmp;
135 free_count = uspi->s_fpb;
136 } else if (free_count > 0 && frag_to_free == tmp - free_count)
137 free_count += uspi->s_fpb;
138 else {
139 ufs_free_blocks (inode, frag_to_free, free_count);
140 frag_to_free = tmp;
141 free_count = uspi->s_fpb;
142 }
143 mark_inode_dirty(inode);
144 }
145
146 if (free_count > 0)
147 ufs_free_blocks (inode, frag_to_free, free_count);
148
149 if (frag3 >= frag4)
150 goto next3;
151
152 /*
153 * Free last free fragments
154 */
155 p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag3));
156 tmp = ufs_data_ptr_to_cpu(sb, p);
157 if (!tmp )
158 ufs_panic(sb, "ufs_truncate_direct", "internal error");
159 frag4 = ufs_fragnum (frag4);
160 ufs_data_ptr_clear(uspi, p);
161
162 ufs_free_fragments (inode, tmp, frag4);
163 mark_inode_dirty(inode);
164 next3:
165
166 UFSD("EXIT: ino %lu\n", inode->i_ino);
167 return retry;
168 }
169
170
ufs_trunc_indirect(struct inode * inode,u64 offset,void * p)171 static int ufs_trunc_indirect(struct inode *inode, u64 offset, void *p)
172 {
173 struct super_block * sb;
174 struct ufs_sb_private_info * uspi;
175 struct ufs_buffer_head * ind_ubh;
176 void *ind;
177 u64 tmp, indirect_block, i, frag_to_free;
178 unsigned free_count;
179 int retry;
180
181 UFSD("ENTER: ino %lu, offset %llu, p: %p\n",
182 inode->i_ino, (unsigned long long)offset, p);
183
184 BUG_ON(!p);
185
186 sb = inode->i_sb;
187 uspi = UFS_SB(sb)->s_uspi;
188
189 frag_to_free = 0;
190 free_count = 0;
191 retry = 0;
192
193 tmp = ufs_data_ptr_to_cpu(sb, p);
194 if (!tmp)
195 return 0;
196 ind_ubh = ubh_bread(sb, tmp, uspi->s_bsize);
197 if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
198 ubh_brelse (ind_ubh);
199 return 1;
200 }
201 if (!ind_ubh) {
202 ufs_data_ptr_clear(uspi, p);
203 return 0;
204 }
205
206 indirect_block = (DIRECT_BLOCK > offset) ? (DIRECT_BLOCK - offset) : 0;
207 for (i = indirect_block; i < uspi->s_apb; i++) {
208 ind = ubh_get_data_ptr(uspi, ind_ubh, i);
209 tmp = ufs_data_ptr_to_cpu(sb, ind);
210 if (!tmp)
211 continue;
212
213 ufs_data_ptr_clear(uspi, ind);
214 ubh_mark_buffer_dirty(ind_ubh);
215 if (free_count == 0) {
216 frag_to_free = tmp;
217 free_count = uspi->s_fpb;
218 } else if (free_count > 0 && frag_to_free == tmp - free_count)
219 free_count += uspi->s_fpb;
220 else {
221 ufs_free_blocks (inode, frag_to_free, free_count);
222 frag_to_free = tmp;
223 free_count = uspi->s_fpb;
224 }
225
226 mark_inode_dirty(inode);
227 }
228
229 if (free_count > 0) {
230 ufs_free_blocks (inode, frag_to_free, free_count);
231 }
232 for (i = 0; i < uspi->s_apb; i++)
233 if (!ufs_is_data_ptr_zero(uspi,
234 ubh_get_data_ptr(uspi, ind_ubh, i)))
235 break;
236 if (i >= uspi->s_apb) {
237 tmp = ufs_data_ptr_to_cpu(sb, p);
238 ufs_data_ptr_clear(uspi, p);
239
240 ufs_free_blocks (inode, tmp, uspi->s_fpb);
241 mark_inode_dirty(inode);
242 ubh_bforget(ind_ubh);
243 ind_ubh = NULL;
244 }
245 if (IS_SYNC(inode) && ind_ubh && ubh_buffer_dirty(ind_ubh))
246 ubh_sync_block(ind_ubh);
247 ubh_brelse (ind_ubh);
248
249 UFSD("EXIT: ino %lu\n", inode->i_ino);
250
251 return retry;
252 }
253
ufs_trunc_dindirect(struct inode * inode,u64 offset,void * p)254 static int ufs_trunc_dindirect(struct inode *inode, u64 offset, void *p)
255 {
256 struct super_block * sb;
257 struct ufs_sb_private_info * uspi;
258 struct ufs_buffer_head *dind_bh;
259 u64 i, tmp, dindirect_block;
260 void *dind;
261 int retry = 0;
262
263 UFSD("ENTER: ino %lu\n", inode->i_ino);
264
265 sb = inode->i_sb;
266 uspi = UFS_SB(sb)->s_uspi;
267
268 dindirect_block = (DIRECT_BLOCK > offset)
269 ? ((DIRECT_BLOCK - offset) >> uspi->s_apbshift) : 0;
270 retry = 0;
271
272 tmp = ufs_data_ptr_to_cpu(sb, p);
273 if (!tmp)
274 return 0;
275 dind_bh = ubh_bread(sb, tmp, uspi->s_bsize);
276 if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
277 ubh_brelse (dind_bh);
278 return 1;
279 }
280 if (!dind_bh) {
281 ufs_data_ptr_clear(uspi, p);
282 return 0;
283 }
284
285 for (i = dindirect_block ; i < uspi->s_apb ; i++) {
286 dind = ubh_get_data_ptr(uspi, dind_bh, i);
287 tmp = ufs_data_ptr_to_cpu(sb, dind);
288 if (!tmp)
289 continue;
290 retry |= ufs_trunc_indirect (inode, offset + (i << uspi->s_apbshift), dind);
291 ubh_mark_buffer_dirty(dind_bh);
292 }
293
294 for (i = 0; i < uspi->s_apb; i++)
295 if (!ufs_is_data_ptr_zero(uspi,
296 ubh_get_data_ptr(uspi, dind_bh, i)))
297 break;
298 if (i >= uspi->s_apb) {
299 tmp = ufs_data_ptr_to_cpu(sb, p);
300 ufs_data_ptr_clear(uspi, p);
301
302 ufs_free_blocks(inode, tmp, uspi->s_fpb);
303 mark_inode_dirty(inode);
304 ubh_bforget(dind_bh);
305 dind_bh = NULL;
306 }
307 if (IS_SYNC(inode) && dind_bh && ubh_buffer_dirty(dind_bh))
308 ubh_sync_block(dind_bh);
309 ubh_brelse (dind_bh);
310
311 UFSD("EXIT: ino %lu\n", inode->i_ino);
312
313 return retry;
314 }
315
ufs_trunc_tindirect(struct inode * inode)316 static int ufs_trunc_tindirect(struct inode *inode)
317 {
318 struct super_block *sb = inode->i_sb;
319 struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
320 struct ufs_inode_info *ufsi = UFS_I(inode);
321 struct ufs_buffer_head * tind_bh;
322 u64 tindirect_block, tmp, i;
323 void *tind, *p;
324 int retry;
325
326 UFSD("ENTER: ino %lu\n", inode->i_ino);
327
328 retry = 0;
329
330 tindirect_block = (DIRECT_BLOCK > (UFS_NDADDR + uspi->s_apb + uspi->s_2apb))
331 ? ((DIRECT_BLOCK - UFS_NDADDR - uspi->s_apb - uspi->s_2apb) >> uspi->s_2apbshift) : 0;
332
333 p = ufs_get_direct_data_ptr(uspi, ufsi, UFS_TIND_BLOCK);
334 if (!(tmp = ufs_data_ptr_to_cpu(sb, p)))
335 return 0;
336 tind_bh = ubh_bread (sb, tmp, uspi->s_bsize);
337 if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
338 ubh_brelse (tind_bh);
339 return 1;
340 }
341 if (!tind_bh) {
342 ufs_data_ptr_clear(uspi, p);
343 return 0;
344 }
345
346 for (i = tindirect_block ; i < uspi->s_apb ; i++) {
347 tind = ubh_get_data_ptr(uspi, tind_bh, i);
348 retry |= ufs_trunc_dindirect(inode, UFS_NDADDR +
349 uspi->s_apb + ((i + 1) << uspi->s_2apbshift), tind);
350 ubh_mark_buffer_dirty(tind_bh);
351 }
352 for (i = 0; i < uspi->s_apb; i++)
353 if (!ufs_is_data_ptr_zero(uspi,
354 ubh_get_data_ptr(uspi, tind_bh, i)))
355 break;
356 if (i >= uspi->s_apb) {
357 tmp = ufs_data_ptr_to_cpu(sb, p);
358 ufs_data_ptr_clear(uspi, p);
359
360 ufs_free_blocks(inode, tmp, uspi->s_fpb);
361 mark_inode_dirty(inode);
362 ubh_bforget(tind_bh);
363 tind_bh = NULL;
364 }
365 if (IS_SYNC(inode) && tind_bh && ubh_buffer_dirty(tind_bh))
366 ubh_sync_block(tind_bh);
367 ubh_brelse (tind_bh);
368
369 UFSD("EXIT: ino %lu\n", inode->i_ino);
370 return retry;
371 }
372
ufs_alloc_lastblock(struct inode * inode)373 static int ufs_alloc_lastblock(struct inode *inode)
374 {
375 int err = 0;
376 struct super_block *sb = inode->i_sb;
377 struct address_space *mapping = inode->i_mapping;
378 struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
379 unsigned i, end;
380 sector_t lastfrag;
381 struct page *lastpage;
382 struct buffer_head *bh;
383 u64 phys64;
384
385 lastfrag = (i_size_read(inode) + uspi->s_fsize - 1) >> uspi->s_fshift;
386
387 if (!lastfrag)
388 goto out;
389
390 lastfrag--;
391
392 lastpage = ufs_get_locked_page(mapping, lastfrag >>
393 (PAGE_CACHE_SHIFT - inode->i_blkbits));
394 if (IS_ERR(lastpage)) {
395 err = -EIO;
396 goto out;
397 }
398
399 end = lastfrag & ((1 << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - 1);
400 bh = page_buffers(lastpage);
401 for (i = 0; i < end; ++i)
402 bh = bh->b_this_page;
403
404
405 err = ufs_getfrag_block(inode, lastfrag, bh, 1);
406
407 if (unlikely(err))
408 goto out_unlock;
409
410 if (buffer_new(bh)) {
411 clear_buffer_new(bh);
412 unmap_underlying_metadata(bh->b_bdev,
413 bh->b_blocknr);
414 /*
415 * we do not zeroize fragment, because of
416 * if it maped to hole, it already contains zeroes
417 */
418 set_buffer_uptodate(bh);
419 mark_buffer_dirty(bh);
420 set_page_dirty(lastpage);
421 }
422
423 if (lastfrag >= UFS_IND_FRAGMENT) {
424 end = uspi->s_fpb - ufs_fragnum(lastfrag) - 1;
425 phys64 = bh->b_blocknr + 1;
426 for (i = 0; i < end; ++i) {
427 bh = sb_getblk(sb, i + phys64);
428 lock_buffer(bh);
429 memset(bh->b_data, 0, sb->s_blocksize);
430 set_buffer_uptodate(bh);
431 mark_buffer_dirty(bh);
432 unlock_buffer(bh);
433 sync_dirty_buffer(bh);
434 brelse(bh);
435 }
436 }
437 out_unlock:
438 ufs_put_locked_page(lastpage);
439 out:
440 return err;
441 }
442
ufs_truncate(struct inode * inode,loff_t old_i_size)443 int ufs_truncate(struct inode *inode, loff_t old_i_size)
444 {
445 struct ufs_inode_info *ufsi = UFS_I(inode);
446 struct super_block *sb = inode->i_sb;
447 struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
448 int retry, err = 0;
449
450 UFSD("ENTER: ino %lu, i_size: %llu, old_i_size: %llu\n",
451 inode->i_ino, (unsigned long long)i_size_read(inode),
452 (unsigned long long)old_i_size);
453
454 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
455 S_ISLNK(inode->i_mode)))
456 return -EINVAL;
457 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
458 return -EPERM;
459
460 err = ufs_alloc_lastblock(inode);
461
462 if (err) {
463 i_size_write(inode, old_i_size);
464 goto out;
465 }
466
467 block_truncate_page(inode->i_mapping, inode->i_size, ufs_getfrag_block);
468
469 while (1) {
470 retry = ufs_trunc_direct(inode);
471 retry |= ufs_trunc_indirect(inode, UFS_IND_BLOCK,
472 ufs_get_direct_data_ptr(uspi, ufsi,
473 UFS_IND_BLOCK));
474 retry |= ufs_trunc_dindirect(inode, UFS_IND_BLOCK + uspi->s_apb,
475 ufs_get_direct_data_ptr(uspi, ufsi,
476 UFS_DIND_BLOCK));
477 retry |= ufs_trunc_tindirect (inode);
478 if (!retry)
479 break;
480 if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
481 ufs_sync_inode (inode);
482 yield();
483 }
484
485 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
486 ufsi->i_lastfrag = DIRECT_FRAGMENT;
487 mark_inode_dirty(inode);
488 out:
489 UFSD("EXIT: err %d\n", err);
490 return err;
491 }
492
ufs_setattr(struct dentry * dentry,struct iattr * attr)493 int ufs_setattr(struct dentry *dentry, struct iattr *attr)
494 {
495 struct inode *inode = dentry->d_inode;
496 unsigned int ia_valid = attr->ia_valid;
497 int error;
498
499 error = inode_change_ok(inode, attr);
500 if (error)
501 return error;
502
503 if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
504 loff_t old_i_size = inode->i_size;
505
506 /* XXX(truncate): truncate_setsize should be called last */
507 truncate_setsize(inode, attr->ia_size);
508
509 lock_ufs(inode->i_sb);
510 error = ufs_truncate(inode, old_i_size);
511 unlock_ufs(inode->i_sb);
512 if (error)
513 return error;
514 }
515
516 setattr_copy(inode, attr);
517 mark_inode_dirty(inode);
518 return 0;
519 }
520
521 const struct inode_operations ufs_file_inode_operations = {
522 .setattr = ufs_setattr,
523 };
524