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9#include "hpfs_fn.h"
10
11static void hpfs_claim_alloc(struct super_block *s, secno sec)
12{
13 struct hpfs_sb_info *sbi = hpfs_sb(s);
14 if (sbi->sb_n_free != (unsigned)-1) {
15 if (unlikely(!sbi->sb_n_free)) {
16 hpfs_error(s, "free count underflow, allocating sector %08x", sec);
17 sbi->sb_n_free = -1;
18 return;
19 }
20 sbi->sb_n_free--;
21 }
22}
23
24static void hpfs_claim_free(struct super_block *s, secno sec)
25{
26 struct hpfs_sb_info *sbi = hpfs_sb(s);
27 if (sbi->sb_n_free != (unsigned)-1) {
28 if (unlikely(sbi->sb_n_free >= sbi->sb_fs_size)) {
29 hpfs_error(s, "free count overflow, freeing sector %08x", sec);
30 sbi->sb_n_free = -1;
31 return;
32 }
33 sbi->sb_n_free++;
34 }
35}
36
37static void hpfs_claim_dirband_alloc(struct super_block *s, secno sec)
38{
39 struct hpfs_sb_info *sbi = hpfs_sb(s);
40 if (sbi->sb_n_free_dnodes != (unsigned)-1) {
41 if (unlikely(!sbi->sb_n_free_dnodes)) {
42 hpfs_error(s, "dirband free count underflow, allocating sector %08x", sec);
43 sbi->sb_n_free_dnodes = -1;
44 return;
45 }
46 sbi->sb_n_free_dnodes--;
47 }
48}
49
50static void hpfs_claim_dirband_free(struct super_block *s, secno sec)
51{
52 struct hpfs_sb_info *sbi = hpfs_sb(s);
53 if (sbi->sb_n_free_dnodes != (unsigned)-1) {
54 if (unlikely(sbi->sb_n_free_dnodes >= sbi->sb_dirband_size / 4)) {
55 hpfs_error(s, "dirband free count overflow, freeing sector %08x", sec);
56 sbi->sb_n_free_dnodes = -1;
57 return;
58 }
59 sbi->sb_n_free_dnodes++;
60 }
61}
62
63
64
65
66
67
68static int chk_if_allocated(struct super_block *s, secno sec, char *msg)
69{
70 struct quad_buffer_head qbh;
71 __le32 *bmp;
72 if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "chk"))) goto fail;
73 if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f)) & 1) {
74 hpfs_error(s, "sector '%s' - %08x not allocated in bitmap", msg, sec);
75 goto fail1;
76 }
77 hpfs_brelse4(&qbh);
78 if (sec >= hpfs_sb(s)->sb_dirband_start && sec < hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {
79 unsigned ssec = (sec - hpfs_sb(s)->sb_dirband_start) / 4;
80 if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto fail;
81 if ((le32_to_cpu(bmp[ssec >> 5]) >> (ssec & 0x1f)) & 1) {
82 hpfs_error(s, "sector '%s' - %08x not allocated in directory bitmap", msg, sec);
83 goto fail1;
84 }
85 hpfs_brelse4(&qbh);
86 }
87 return 0;
88 fail1:
89 hpfs_brelse4(&qbh);
90 fail:
91 return 1;
92}
93
94
95
96
97
98
99int hpfs_chk_sectors(struct super_block *s, secno start, int len, char *msg)
100{
101 if (start + len < start || start < 0x12 ||
102 start + len > hpfs_sb(s)->sb_fs_size) {
103 hpfs_error(s, "sector(s) '%s' badly placed at %08x", msg, start);
104 return 1;
105 }
106 if (hpfs_sb(s)->sb_chk>=2) {
107 int i;
108 for (i = 0; i < len; i++)
109 if (chk_if_allocated(s, start + i, msg)) return 1;
110 }
111 return 0;
112}
113
114static secno alloc_in_bmp(struct super_block *s, secno near, unsigned n, unsigned forward)
115{
116 struct quad_buffer_head qbh;
117 __le32 *bmp;
118 unsigned bs = near & ~0x3fff;
119 unsigned nr = (near & 0x3fff) & ~(n - 1);
120
121 unsigned i, q;
122 int a, b;
123 secno ret = 0;
124 if (n != 1 && n != 4) {
125 hpfs_error(s, "Bad allocation size: %d", n);
126 return 0;
127 }
128 if (bs != ~0x3fff) {
129 if (!(bmp = hpfs_map_bitmap(s, near >> 14, &qbh, "aib"))) goto uls;
130 } else {
131 if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto uls;
132 }
133 if (!tstbits(bmp, nr, n + forward)) {
134 ret = bs + nr;
135 goto rt;
136 }
137 q = nr + n; b = 0;
138 while ((a = tstbits(bmp, q, n + forward)) != 0) {
139 q += a;
140 if (n != 1) q = ((q-1)&~(n-1))+n;
141 if (!b) {
142 if (q>>5 != nr>>5) {
143 b = 1;
144 q = nr & 0x1f;
145 }
146 } else if (q > nr) break;
147 }
148 if (!a) {
149 ret = bs + q;
150 goto rt;
151 }
152 nr >>= 5;
153
154 i = nr;
155 do {
156 if (!le32_to_cpu(bmp[i])) goto cont;
157 if (n + forward >= 0x3f && le32_to_cpu(bmp[i]) != 0xffffffff) goto cont;
158 q = i<<5;
159 if (i > 0) {
160 unsigned k = le32_to_cpu(bmp[i-1]);
161 while (k & 0x80000000) {
162 q--; k <<= 1;
163 }
164 }
165 if (n != 1) q = ((q-1)&~(n-1))+n;
166 while ((a = tstbits(bmp, q, n + forward)) != 0) {
167 q += a;
168 if (n != 1) q = ((q-1)&~(n-1))+n;
169 if (q>>5 > i) break;
170 }
171 if (!a) {
172 ret = bs + q;
173 goto rt;
174 }
175 cont:
176 i++, i &= 0x1ff;
177 } while (i != nr);
178 rt:
179 if (ret) {
180 if (hpfs_sb(s)->sb_chk && ((ret >> 14) != (bs >> 14) || (le32_to_cpu(bmp[(ret & 0x3fff) >> 5]) | ~(((1 << n) - 1) << (ret & 0x1f))) != 0xffffffff)) {
181 hpfs_error(s, "Allocation doesn't work! Wanted %d, allocated at %08x", n, ret);
182 ret = 0;
183 goto b;
184 }
185 bmp[(ret & 0x3fff) >> 5] &= cpu_to_le32(~(((1 << n) - 1) << (ret & 0x1f)));
186 hpfs_mark_4buffers_dirty(&qbh);
187 }
188 b:
189 hpfs_brelse4(&qbh);
190 uls:
191 return ret;
192}
193
194
195
196
197
198
199
200
201
202secno hpfs_alloc_sector(struct super_block *s, secno near, unsigned n, int forward)
203{
204 secno sec;
205 int i;
206 unsigned n_bmps;
207 struct hpfs_sb_info *sbi = hpfs_sb(s);
208 int f_p = 0;
209 int near_bmp;
210 if (forward < 0) {
211 forward = -forward;
212 f_p = 1;
213 }
214 n_bmps = (sbi->sb_fs_size + 0x4000 - 1) >> 14;
215 if (near && near < sbi->sb_fs_size) {
216 if ((sec = alloc_in_bmp(s, near, n, f_p ? forward : forward/4))) goto ret;
217 near_bmp = near >> 14;
218 } else near_bmp = n_bmps / 2;
219
220
221
222
223
224
225
226
227 if (!f_p) if (forward > sbi->sb_max_fwd_alloc) forward = sbi->sb_max_fwd_alloc;
228 less_fwd:
229 for (i = 0; i < n_bmps; i++) {
230 if (near_bmp+i < n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i) << 14, n, forward)))) {
231 sbi->sb_c_bitmap = near_bmp+i;
232 goto ret;
233 }
234 if (!forward) {
235 if (near_bmp-i-1 >= 0 && ((sec = alloc_in_bmp(s, (near_bmp-i-1) << 14, n, forward)))) {
236 sbi->sb_c_bitmap = near_bmp-i-1;
237 goto ret;
238 }
239 } else {
240 if (near_bmp+i >= n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i-n_bmps) << 14, n, forward)))) {
241 sbi->sb_c_bitmap = near_bmp+i-n_bmps;
242 goto ret;
243 }
244 }
245 if (i == 1 && sbi->sb_c_bitmap != -1 && ((sec = alloc_in_bmp(s, (sbi->sb_c_bitmap) << 14, n, forward)))) {
246 goto ret;
247 }
248 }
249 if (!f_p) {
250 if (forward) {
251 sbi->sb_max_fwd_alloc = forward * 3 / 4;
252 forward /= 2;
253 goto less_fwd;
254 }
255 }
256 sec = 0;
257 ret:
258 if (sec) {
259 i = 0;
260 do
261 hpfs_claim_alloc(s, sec + i);
262 while (unlikely(++i < n));
263 }
264 if (sec && f_p) {
265 for (i = 0; i < forward; i++) {
266 if (!hpfs_alloc_if_possible(s, sec + n + i)) {
267 hpfs_error(s, "Prealloc doesn't work! Wanted %d, allocated at %08x, can't allocate %d", forward, sec, i);
268 sec = 0;
269 break;
270 }
271 }
272 }
273 return sec;
274}
275
276static secno alloc_in_dirband(struct super_block *s, secno near)
277{
278 unsigned nr = near;
279 secno sec;
280 struct hpfs_sb_info *sbi = hpfs_sb(s);
281 if (nr < sbi->sb_dirband_start)
282 nr = sbi->sb_dirband_start;
283 if (nr >= sbi->sb_dirband_start + sbi->sb_dirband_size)
284 nr = sbi->sb_dirband_start + sbi->sb_dirband_size - 4;
285 nr -= sbi->sb_dirband_start;
286 nr >>= 2;
287 sec = alloc_in_bmp(s, (~0x3fff) | nr, 1, 0);
288 if (!sec) return 0;
289 hpfs_claim_dirband_alloc(s, sec);
290 return ((sec & 0x3fff) << 2) + sbi->sb_dirband_start;
291}
292
293
294
295int hpfs_alloc_if_possible(struct super_block *s, secno sec)
296{
297 struct quad_buffer_head qbh;
298 __le32 *bmp;
299 if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "aip"))) goto end;
300 if (le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) & (1 << (sec & 0x1f))) {
301 bmp[(sec & 0x3fff) >> 5] &= cpu_to_le32(~(1 << (sec & 0x1f)));
302 hpfs_mark_4buffers_dirty(&qbh);
303 hpfs_brelse4(&qbh);
304 hpfs_claim_alloc(s, sec);
305 return 1;
306 }
307 hpfs_brelse4(&qbh);
308 end:
309 return 0;
310}
311
312
313
314void hpfs_free_sectors(struct super_block *s, secno sec, unsigned n)
315{
316 struct quad_buffer_head qbh;
317 __le32 *bmp;
318 struct hpfs_sb_info *sbi = hpfs_sb(s);
319
320 if (!n) return;
321 if (sec < 0x12) {
322 hpfs_error(s, "Trying to free reserved sector %08x", sec);
323 return;
324 }
325 sbi->sb_max_fwd_alloc += n > 0xffff ? 0xffff : n;
326 if (sbi->sb_max_fwd_alloc > 0xffffff) sbi->sb_max_fwd_alloc = 0xffffff;
327 new_map:
328 if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "free"))) {
329 return;
330 }
331 new_tst:
332 if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f) & 1)) {
333 hpfs_error(s, "sector %08x not allocated", sec);
334 hpfs_brelse4(&qbh);
335 return;
336 }
337 bmp[(sec & 0x3fff) >> 5] |= cpu_to_le32(1 << (sec & 0x1f));
338 hpfs_claim_free(s, sec);
339 if (!--n) {
340 hpfs_mark_4buffers_dirty(&qbh);
341 hpfs_brelse4(&qbh);
342 return;
343 }
344 if (!(++sec & 0x3fff)) {
345 hpfs_mark_4buffers_dirty(&qbh);
346 hpfs_brelse4(&qbh);
347 goto new_map;
348 }
349 goto new_tst;
350}
351
352
353
354
355
356
357
358int hpfs_check_free_dnodes(struct super_block *s, int n)
359{
360 int n_bmps = (hpfs_sb(s)->sb_fs_size + 0x4000 - 1) >> 14;
361 int b = hpfs_sb(s)->sb_c_bitmap & 0x0fffffff;
362 int i, j;
363 __le32 *bmp;
364 struct quad_buffer_head qbh;
365 if ((bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
366 for (j = 0; j < 512; j++) {
367 unsigned k;
368 if (!le32_to_cpu(bmp[j])) continue;
369 for (k = le32_to_cpu(bmp[j]); k; k >>= 1) if (k & 1) if (!--n) {
370 hpfs_brelse4(&qbh);
371 return 0;
372 }
373 }
374 }
375 hpfs_brelse4(&qbh);
376 i = 0;
377 if (hpfs_sb(s)->sb_c_bitmap != -1) {
378 bmp = hpfs_map_bitmap(s, b, &qbh, "chkdn1");
379 goto chk_bmp;
380 }
381 chk_next:
382 if (i == b) i++;
383 if (i >= n_bmps) return 1;
384 bmp = hpfs_map_bitmap(s, i, &qbh, "chkdn2");
385 chk_bmp:
386 if (bmp) {
387 for (j = 0; j < 512; j++) {
388 u32 k;
389 if (!le32_to_cpu(bmp[j])) continue;
390 for (k = 0xf; k; k <<= 4)
391 if ((le32_to_cpu(bmp[j]) & k) == k) {
392 if (!--n) {
393 hpfs_brelse4(&qbh);
394 return 0;
395 }
396 }
397 }
398 hpfs_brelse4(&qbh);
399 }
400 i++;
401 goto chk_next;
402}
403
404void hpfs_free_dnode(struct super_block *s, dnode_secno dno)
405{
406 if (hpfs_sb(s)->sb_chk) if (dno & 3) {
407 hpfs_error(s, "hpfs_free_dnode: dnode %08x not aligned", dno);
408 return;
409 }
410 if (dno < hpfs_sb(s)->sb_dirband_start ||
411 dno >= hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {
412 hpfs_free_sectors(s, dno, 4);
413 } else {
414 struct quad_buffer_head qbh;
415 __le32 *bmp;
416 unsigned ssec = (dno - hpfs_sb(s)->sb_dirband_start) / 4;
417 if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
418 return;
419 }
420 bmp[ssec >> 5] |= cpu_to_le32(1 << (ssec & 0x1f));
421 hpfs_mark_4buffers_dirty(&qbh);
422 hpfs_brelse4(&qbh);
423 hpfs_claim_dirband_free(s, dno);
424 }
425}
426
427struct dnode *hpfs_alloc_dnode(struct super_block *s, secno near,
428 dnode_secno *dno, struct quad_buffer_head *qbh)
429{
430 struct dnode *d;
431 if (hpfs_get_free_dnodes(s) > FREE_DNODES_ADD) {
432 if (!(*dno = alloc_in_dirband(s, near)))
433 if (!(*dno = hpfs_alloc_sector(s, near, 4, 0))) return NULL;
434 } else {
435 if (!(*dno = hpfs_alloc_sector(s, near, 4, 0)))
436 if (!(*dno = alloc_in_dirband(s, near))) return NULL;
437 }
438 if (!(d = hpfs_get_4sectors(s, *dno, qbh))) {
439 hpfs_free_dnode(s, *dno);
440 return NULL;
441 }
442 memset(d, 0, 2048);
443 d->magic = cpu_to_le32(DNODE_MAGIC);
444 d->first_free = cpu_to_le32(52);
445 d->dirent[0] = 32;
446 d->dirent[2] = 8;
447 d->dirent[30] = 1;
448 d->dirent[31] = 255;
449 d->self = cpu_to_le32(*dno);
450 return d;
451}
452
453struct fnode *hpfs_alloc_fnode(struct super_block *s, secno near, fnode_secno *fno,
454 struct buffer_head **bh)
455{
456 struct fnode *f;
457 if (!(*fno = hpfs_alloc_sector(s, near, 1, FNODE_ALLOC_FWD))) return NULL;
458 if (!(f = hpfs_get_sector(s, *fno, bh))) {
459 hpfs_free_sectors(s, *fno, 1);
460 return NULL;
461 }
462 memset(f, 0, 512);
463 f->magic = cpu_to_le32(FNODE_MAGIC);
464 f->ea_offs = cpu_to_le16(0xc4);
465 f->btree.n_free_nodes = 8;
466 f->btree.first_free = cpu_to_le16(8);
467 return f;
468}
469
470struct anode *hpfs_alloc_anode(struct super_block *s, secno near, anode_secno *ano,
471 struct buffer_head **bh)
472{
473 struct anode *a;
474 if (!(*ano = hpfs_alloc_sector(s, near, 1, ANODE_ALLOC_FWD))) return NULL;
475 if (!(a = hpfs_get_sector(s, *ano, bh))) {
476 hpfs_free_sectors(s, *ano, 1);
477 return NULL;
478 }
479 memset(a, 0, 512);
480 a->magic = cpu_to_le32(ANODE_MAGIC);
481 a->self = cpu_to_le32(*ano);
482 a->btree.n_free_nodes = 40;
483 a->btree.n_used_nodes = 0;
484 a->btree.first_free = cpu_to_le16(8);
485 return a;
486}
487
488static unsigned find_run(__le32 *bmp, unsigned *idx)
489{
490 unsigned len;
491 while (tstbits(bmp, *idx, 1)) {
492 (*idx)++;
493 if (unlikely(*idx >= 0x4000))
494 return 0;
495 }
496 len = 1;
497 while (!tstbits(bmp, *idx + len, 1))
498 len++;
499 return len;
500}
501
502static int do_trim(struct super_block *s, secno start, unsigned len, secno limit_start, secno limit_end, unsigned minlen, unsigned *result)
503{
504 int err;
505 secno end;
506 if (fatal_signal_pending(current))
507 return -EINTR;
508 end = start + len;
509 if (start < limit_start)
510 start = limit_start;
511 if (end > limit_end)
512 end = limit_end;
513 if (start >= end)
514 return 0;
515 if (end - start < minlen)
516 return 0;
517 err = sb_issue_discard(s, start, end - start, GFP_NOFS, 0);
518 if (err)
519 return err;
520 *result += end - start;
521 return 0;
522}
523
524int hpfs_trim_fs(struct super_block *s, u64 start, u64 end, u64 minlen, unsigned *result)
525{
526 int err = 0;
527 struct hpfs_sb_info *sbi = hpfs_sb(s);
528 unsigned idx, len, start_bmp, end_bmp;
529 __le32 *bmp;
530 struct quad_buffer_head qbh;
531
532 *result = 0;
533 if (!end || end > sbi->sb_fs_size)
534 end = sbi->sb_fs_size;
535 if (start >= sbi->sb_fs_size)
536 return 0;
537 if (minlen > 0x4000)
538 return 0;
539 if (start < sbi->sb_dirband_start + sbi->sb_dirband_size && end > sbi->sb_dirband_start) {
540 hpfs_lock(s);
541 if (s->s_flags & MS_RDONLY) {
542 err = -EROFS;
543 goto unlock_1;
544 }
545 if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
546 err = -EIO;
547 goto unlock_1;
548 }
549 idx = 0;
550 while ((len = find_run(bmp, &idx)) && !err) {
551 err = do_trim(s, sbi->sb_dirband_start + idx * 4, len * 4, start, end, minlen, result);
552 idx += len;
553 }
554 hpfs_brelse4(&qbh);
555unlock_1:
556 hpfs_unlock(s);
557 }
558 start_bmp = start >> 14;
559 end_bmp = (end + 0x3fff) >> 14;
560 while (start_bmp < end_bmp && !err) {
561 hpfs_lock(s);
562 if (s->s_flags & MS_RDONLY) {
563 err = -EROFS;
564 goto unlock_2;
565 }
566 if (!(bmp = hpfs_map_bitmap(s, start_bmp, &qbh, "trim"))) {
567 err = -EIO;
568 goto unlock_2;
569 }
570 idx = 0;
571 while ((len = find_run(bmp, &idx)) && !err) {
572 err = do_trim(s, (start_bmp << 14) + idx, len, start, end, minlen, result);
573 idx += len;
574 }
575 hpfs_brelse4(&qbh);
576unlock_2:
577 hpfs_unlock(s);
578 start_bmp++;
579 }
580 return err;
581}
582
