1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/hpfs/anode.c
4 *
5 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6 *
7 * handling HPFS anode tree that contains file allocation info
8 */
9
10#include "hpfs_fn.h"
11
12/* Find a sector in allocation tree */
13
14secno hpfs_bplus_lookup(struct super_block *s, struct inode *inode,
15 struct bplus_header *btree, unsigned sec,
16 struct buffer_head *bh)
17{
18 anode_secno a = -1;
19 struct anode *anode;
20 int i;
21 int c1, c2 = 0;
22 go_down:
23 if (hpfs_sb(sb: s)->sb_chk) if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_bplus_lookup")) return -1;
24 if (bp_internal(bp: btree)) {
25 for (i = 0; i < btree->n_used_nodes; i++)
26 if (le32_to_cpu(btree->u.internal[i].file_secno) > sec) {
27 a = le32_to_cpu(btree->u.internal[i].down);
28 brelse(bh);
29 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
30 btree = &anode->btree;
31 goto go_down;
32 }
33 hpfs_error(s, "sector %08x not found in internal anode %08x", sec, a);
34 brelse(bh);
35 return -1;
36 }
37 for (i = 0; i < btree->n_used_nodes; i++)
38 if (le32_to_cpu(btree->u.external[i].file_secno) <= sec &&
39 le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > sec) {
40 a = le32_to_cpu(btree->u.external[i].disk_secno) + sec - le32_to_cpu(btree->u.external[i].file_secno);
41 if (hpfs_sb(sb: s)->sb_chk) if (hpfs_chk_sectors(s, a, 1, "data")) {
42 brelse(bh);
43 return -1;
44 }
45 if (inode) {
46 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
47 hpfs_inode->i_file_sec = le32_to_cpu(btree->u.external[i].file_secno);
48 hpfs_inode->i_disk_sec = le32_to_cpu(btree->u.external[i].disk_secno);
49 hpfs_inode->i_n_secs = le32_to_cpu(btree->u.external[i].length);
50 }
51 brelse(bh);
52 return a;
53 }
54 hpfs_error(s, "sector %08x not found in external anode %08x", sec, a);
55 brelse(bh);
56 return -1;
57}
58
59/* Add a sector to tree */
60
61secno hpfs_add_sector_to_btree(struct super_block *s, secno node, int fnod, unsigned fsecno)
62{
63 struct bplus_header *btree;
64 struct anode *anode = NULL, *ranode = NULL;
65 struct fnode *fnode;
66 anode_secno a, na = -1, ra, up = -1;
67 secno se;
68 struct buffer_head *bh, *bh1, *bh2;
69 int n;
70 unsigned fs;
71 int c1, c2 = 0;
72 if (fnod) {
73 if (!(fnode = hpfs_map_fnode(s, node, &bh))) return -1;
74 btree = &fnode->btree;
75 } else {
76 if (!(anode = hpfs_map_anode(s, node, &bh))) return -1;
77 btree = &anode->btree;
78 }
79 a = node;
80 go_down:
81 if ((n = btree->n_used_nodes - 1) < -!!fnod) {
82 hpfs_error(s, "anode %08x has no entries", a);
83 brelse(bh);
84 return -1;
85 }
86 if (bp_internal(bp: btree)) {
87 a = le32_to_cpu(btree->u.internal[n].down);
88 btree->u.internal[n].file_secno = cpu_to_le32(-1);
89 mark_buffer_dirty(bh);
90 brelse(bh);
91 if (hpfs_sb(sb: s)->sb_chk)
92 if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_add_sector_to_btree #1")) return -1;
93 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
94 btree = &anode->btree;
95 goto go_down;
96 }
97 if (n >= 0) {
98 if (le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length) != fsecno) {
99 hpfs_error(s, "allocated size %08x, trying to add sector %08x, %cnode %08x",
100 le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length), fsecno,
101 fnod?'f':'a', node);
102 brelse(bh);
103 return -1;
104 }
105 if (hpfs_alloc_if_possible(s, se = le32_to_cpu(btree->u.external[n].disk_secno) + le32_to_cpu(btree->u.external[n].length))) {
106 le32_add_cpu(var: &btree->u.external[n].length, val: 1);
107 mark_buffer_dirty(bh);
108 brelse(bh);
109 return se;
110 }
111 } else {
112 if (fsecno) {
113 hpfs_error(s, "empty file %08x, trying to add sector %08x", node, fsecno);
114 brelse(bh);
115 return -1;
116 }
117 se = !fnod ? node : (node + 16384) & ~16383;
118 }
119 if (!(se = hpfs_alloc_sector(s, se, 1, fsecno*ALLOC_M>ALLOC_FWD_MAX ? ALLOC_FWD_MAX : fsecno*ALLOC_M<ALLOC_FWD_MIN ? ALLOC_FWD_MIN : fsecno*ALLOC_M))) {
120 brelse(bh);
121 return -1;
122 }
123 fs = n < 0 ? 0 : le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length);
124 if (!btree->n_free_nodes) {
125 up = a != node ? le32_to_cpu(anode->up) : -1;
126 if (!(anode = hpfs_alloc_anode(s, a, &na, &bh1))) {
127 brelse(bh);
128 hpfs_free_sectors(s, se, 1);
129 return -1;
130 }
131 if (a == node && fnod) {
132 anode->up = cpu_to_le32(node);
133 anode->btree.flags |= BP_fnode_parent;
134 anode->btree.n_used_nodes = btree->n_used_nodes;
135 anode->btree.first_free = btree->first_free;
136 anode->btree.n_free_nodes = 40 - anode->btree.n_used_nodes;
137 memcpy(&anode->u, &btree->u, btree->n_used_nodes * 12);
138 btree->flags |= BP_internal;
139 btree->n_free_nodes = 11;
140 btree->n_used_nodes = 1;
141 btree->first_free = cpu_to_le16((char *)&(btree->u.internal[1]) - (char *)btree);
142 btree->u.internal[0].file_secno = cpu_to_le32(-1);
143 btree->u.internal[0].down = cpu_to_le32(na);
144 mark_buffer_dirty(bh);
145 } else if (!(ranode = hpfs_alloc_anode(s, /*a*/0, &ra, &bh2))) {
146 brelse(bh);
147 brelse(bh: bh1);
148 hpfs_free_sectors(s, se, 1);
149 hpfs_free_sectors(s, na, 1);
150 return -1;
151 }
152 brelse(bh);
153 bh = bh1;
154 btree = &anode->btree;
155 }
156 btree->n_free_nodes--; n = btree->n_used_nodes++;
157 le16_add_cpu(var: &btree->first_free, val: 12);
158 btree->u.external[n].disk_secno = cpu_to_le32(se);
159 btree->u.external[n].file_secno = cpu_to_le32(fs);
160 btree->u.external[n].length = cpu_to_le32(1);
161 mark_buffer_dirty(bh);
162 brelse(bh);
163 if ((a == node && fnod) || na == -1) return se;
164 c2 = 0;
165 while (up != (anode_secno)-1) {
166 struct anode *new_anode;
167 if (hpfs_sb(sb: s)->sb_chk)
168 if (hpfs_stop_cycles(s, up, &c1, &c2, "hpfs_add_sector_to_btree #2")) return -1;
169 if (up != node || !fnod) {
170 if (!(anode = hpfs_map_anode(s, up, &bh))) return -1;
171 btree = &anode->btree;
172 } else {
173 if (!(fnode = hpfs_map_fnode(s, up, &bh))) return -1;
174 btree = &fnode->btree;
175 }
176 if (btree->n_free_nodes) {
177 btree->n_free_nodes--; n = btree->n_used_nodes++;
178 le16_add_cpu(var: &btree->first_free, val: 8);
179 btree->u.internal[n].file_secno = cpu_to_le32(-1);
180 btree->u.internal[n].down = cpu_to_le32(na);
181 btree->u.internal[n-1].file_secno = cpu_to_le32(fs);
182 mark_buffer_dirty(bh);
183 brelse(bh);
184 brelse(bh: bh2);
185 hpfs_free_sectors(s, ra, 1);
186 if ((anode = hpfs_map_anode(s, na, &bh))) {
187 anode->up = cpu_to_le32(up);
188 if (up == node && fnod)
189 anode->btree.flags |= BP_fnode_parent;
190 else
191 anode->btree.flags &= ~BP_fnode_parent;
192 mark_buffer_dirty(bh);
193 brelse(bh);
194 }
195 return se;
196 }
197 up = up != node ? le32_to_cpu(anode->up) : -1;
198 btree->u.internal[btree->n_used_nodes - 1].file_secno = cpu_to_le32(/*fs*/-1);
199 mark_buffer_dirty(bh);
200 brelse(bh);
201 a = na;
202 if ((new_anode = hpfs_alloc_anode(s, a, &na, &bh))) {
203 anode = new_anode;
204 /*anode->up = cpu_to_le32(up != -1 ? up : ra);*/
205 anode->btree.flags |= BP_internal;
206 anode->btree.n_used_nodes = 1;
207 anode->btree.n_free_nodes = 59;
208 anode->btree.first_free = cpu_to_le16(16);
209 anode->btree.u.internal[0].down = cpu_to_le32(a);
210 anode->btree.u.internal[0].file_secno = cpu_to_le32(-1);
211 mark_buffer_dirty(bh);
212 brelse(bh);
213 if ((anode = hpfs_map_anode(s, a, &bh))) {
214 anode->up = cpu_to_le32(na);
215 mark_buffer_dirty(bh);
216 brelse(bh);
217 }
218 } else na = a;
219 }
220 if ((anode = hpfs_map_anode(s, na, &bh))) {
221 anode->up = cpu_to_le32(node);
222 if (fnod)
223 anode->btree.flags |= BP_fnode_parent;
224 mark_buffer_dirty(bh);
225 brelse(bh);
226 }
227 if (!fnod) {
228 if (!(anode = hpfs_map_anode(s, node, &bh))) {
229 brelse(bh: bh2);
230 return -1;
231 }
232 btree = &anode->btree;
233 } else {
234 if (!(fnode = hpfs_map_fnode(s, node, &bh))) {
235 brelse(bh: bh2);
236 return -1;
237 }
238 btree = &fnode->btree;
239 }
240 ranode->up = cpu_to_le32(node);
241 memcpy(&ranode->btree, btree, le16_to_cpu(btree->first_free));
242 if (fnod)
243 ranode->btree.flags |= BP_fnode_parent;
244 ranode->btree.n_free_nodes = (bp_internal(bp: &ranode->btree) ? 60 : 40) - ranode->btree.n_used_nodes;
245 if (bp_internal(bp: &ranode->btree)) for (n = 0; n < ranode->btree.n_used_nodes; n++) {
246 struct anode *unode;
247 if ((unode = hpfs_map_anode(s, le32_to_cpu(ranode->u.internal[n].down), &bh1))) {
248 unode->up = cpu_to_le32(ra);
249 unode->btree.flags &= ~BP_fnode_parent;
250 mark_buffer_dirty(bh: bh1);
251 brelse(bh: bh1);
252 }
253 }
254 btree->flags |= BP_internal;
255 btree->n_free_nodes = fnod ? 10 : 58;
256 btree->n_used_nodes = 2;
257 btree->first_free = cpu_to_le16((char *)&btree->u.internal[2] - (char *)btree);
258 btree->u.internal[0].file_secno = cpu_to_le32(fs);
259 btree->u.internal[0].down = cpu_to_le32(ra);
260 btree->u.internal[1].file_secno = cpu_to_le32(-1);
261 btree->u.internal[1].down = cpu_to_le32(na);
262 mark_buffer_dirty(bh);
263 brelse(bh);
264 mark_buffer_dirty(bh: bh2);
265 brelse(bh: bh2);
266 return se;
267}
268
269/*
270 * Remove allocation tree. Recursion would look much nicer but
271 * I want to avoid it because it can cause stack overflow.
272 */
273
274void hpfs_remove_btree(struct super_block *s, struct bplus_header *btree)
275{
276 struct bplus_header *btree1 = btree;
277 struct anode *anode = NULL;
278 anode_secno ano = 0, oano;
279 struct buffer_head *bh;
280 int level = 0;
281 int pos = 0;
282 int i;
283 int c1, c2 = 0;
284 int d1, d2;
285 go_down:
286 d2 = 0;
287 while (bp_internal(bp: btree1)) {
288 ano = le32_to_cpu(btree1->u.internal[pos].down);
289 if (level) brelse(bh);
290 if (hpfs_sb(sb: s)->sb_chk)
291 if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1"))
292 return;
293 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
294 btree1 = &anode->btree;
295 level++;
296 pos = 0;
297 }
298 for (i = 0; i < btree1->n_used_nodes; i++)
299 hpfs_free_sectors(s, le32_to_cpu(btree1->u.external[i].disk_secno), le32_to_cpu(btree1->u.external[i].length));
300 go_up:
301 if (!level) return;
302 brelse(bh);
303 if (hpfs_sb(sb: s)->sb_chk)
304 if (hpfs_stop_cycles(s, ano, &c1, &c2, "hpfs_remove_btree #2")) return;
305 hpfs_free_sectors(s, ano, 1);
306 oano = ano;
307 ano = le32_to_cpu(anode->up);
308 if (--level) {
309 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
310 btree1 = &anode->btree;
311 } else btree1 = btree;
312 for (i = 0; i < btree1->n_used_nodes; i++) {
313 if (le32_to_cpu(btree1->u.internal[i].down) == oano) {
314 if ((pos = i + 1) < btree1->n_used_nodes)
315 goto go_down;
316 else
317 goto go_up;
318 }
319 }
320 hpfs_error(s,
321 "reference to anode %08x not found in anode %08x "
322 "(probably bad up pointer)",
323 oano, level ? ano : -1);
324 if (level)
325 brelse(bh);
326}
327
328/* Just a wrapper around hpfs_bplus_lookup .. used for reading eas */
329
330static secno anode_lookup(struct super_block *s, anode_secno a, unsigned sec)
331{
332 struct anode *anode;
333 struct buffer_head *bh;
334 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
335 return hpfs_bplus_lookup(s, NULL, btree: &anode->btree, sec, bh);
336}
337
338int hpfs_ea_read(struct super_block *s, secno a, int ano, unsigned pos,
339 unsigned len, char *buf)
340{
341 struct buffer_head *bh;
342 char *data;
343 secno sec;
344 unsigned l;
345 while (len) {
346 if (ano) {
347 if ((sec = anode_lookup(s, a, sec: pos >> 9)) == -1)
348 return -1;
349 } else sec = a + (pos >> 9);
350 if (hpfs_sb(sb: s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #1")) return -1;
351 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
352 return -1;
353 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
354 memcpy(buf, data + (pos & 0x1ff), l);
355 brelse(bh);
356 buf += l; pos += l; len -= l;
357 }
358 return 0;
359}
360
361int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos,
362 unsigned len, const char *buf)
363{
364 struct buffer_head *bh;
365 char *data;
366 secno sec;
367 unsigned l;
368 while (len) {
369 if (ano) {
370 if ((sec = anode_lookup(s, a, sec: pos >> 9)) == -1)
371 return -1;
372 } else sec = a + (pos >> 9);
373 if (hpfs_sb(sb: s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #2")) return -1;
374 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
375 return -1;
376 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
377 memcpy(data + (pos & 0x1ff), buf, l);
378 mark_buffer_dirty(bh);
379 brelse(bh);
380 buf += l; pos += l; len -= l;
381 }
382 return 0;
383}
384
385void hpfs_ea_remove(struct super_block *s, secno a, int ano, unsigned len)
386{
387 struct anode *anode;
388 struct buffer_head *bh;
389 if (ano) {
390 if (!(anode = hpfs_map_anode(s, a, &bh))) return;
391 hpfs_remove_btree(s, btree: &anode->btree);
392 brelse(bh);
393 hpfs_free_sectors(s, a, 1);
394 } else hpfs_free_sectors(s, a, (len + 511) >> 9);
395}
396
397/* Truncate allocation tree. Doesn't join anodes - I hope it doesn't matter */
398
399void hpfs_truncate_btree(struct super_block *s, secno f, int fno, unsigned secs)
400{
401 struct fnode *fnode;
402 struct anode *anode;
403 struct buffer_head *bh;
404 struct bplus_header *btree;
405 anode_secno node = f;
406 int i, j, nodes;
407 int c1, c2 = 0;
408 if (fno) {
409 if (!(fnode = hpfs_map_fnode(s, f, &bh))) return;
410 btree = &fnode->btree;
411 } else {
412 if (!(anode = hpfs_map_anode(s, f, &bh))) return;
413 btree = &anode->btree;
414 }
415 if (!secs) {
416 hpfs_remove_btree(s, btree);
417 if (fno) {
418 btree->n_free_nodes = 8;
419 btree->n_used_nodes = 0;
420 btree->first_free = cpu_to_le16(8);
421 btree->flags &= ~BP_internal;
422 mark_buffer_dirty(bh);
423 } else hpfs_free_sectors(s, f, 1);
424 brelse(bh);
425 return;
426 }
427 while (bp_internal(bp: btree)) {
428 nodes = btree->n_used_nodes + btree->n_free_nodes;
429 for (i = 0; i < btree->n_used_nodes; i++)
430 if (le32_to_cpu(btree->u.internal[i].file_secno) >= secs) goto f;
431 brelse(bh);
432 hpfs_error(s, "internal btree %08x doesn't end with -1", node);
433 return;
434 f:
435 for (j = i + 1; j < btree->n_used_nodes; j++)
436 hpfs_ea_remove(s, le32_to_cpu(btree->u.internal[j].down), ano: 1, len: 0);
437 btree->n_used_nodes = i + 1;
438 btree->n_free_nodes = nodes - btree->n_used_nodes;
439 btree->first_free = cpu_to_le16(8 + 8 * btree->n_used_nodes);
440 mark_buffer_dirty(bh);
441 if (btree->u.internal[i].file_secno == cpu_to_le32(secs)) {
442 brelse(bh);
443 return;
444 }
445 node = le32_to_cpu(btree->u.internal[i].down);
446 brelse(bh);
447 if (hpfs_sb(sb: s)->sb_chk)
448 if (hpfs_stop_cycles(s, node, &c1, &c2, "hpfs_truncate_btree"))
449 return;
450 if (!(anode = hpfs_map_anode(s, node, &bh))) return;
451 btree = &anode->btree;
452 }
453 nodes = btree->n_used_nodes + btree->n_free_nodes;
454 for (i = 0; i < btree->n_used_nodes; i++)
455 if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) >= secs) goto ff;
456 brelse(bh);
457 return;
458 ff:
459 if (secs <= le32_to_cpu(btree->u.external[i].file_secno)) {
460 hpfs_error(s, "there is an allocation error in file %08x, sector %08x", f, secs);
461 if (i) i--;
462 }
463 else if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > secs) {
464 hpfs_free_sectors(s, le32_to_cpu(btree->u.external[i].disk_secno) + secs -
465 le32_to_cpu(btree->u.external[i].file_secno), le32_to_cpu(btree->u.external[i].length)
466 - secs + le32_to_cpu(btree->u.external[i].file_secno)); /* I hope gcc optimizes this :-) */
467 btree->u.external[i].length = cpu_to_le32(secs - le32_to_cpu(btree->u.external[i].file_secno));
468 }
469 for (j = i + 1; j < btree->n_used_nodes; j++)
470 hpfs_free_sectors(s, le32_to_cpu(btree->u.external[j].disk_secno), le32_to_cpu(btree->u.external[j].length));
471 btree->n_used_nodes = i + 1;
472 btree->n_free_nodes = nodes - btree->n_used_nodes;
473 btree->first_free = cpu_to_le16(8 + 12 * btree->n_used_nodes);
474 mark_buffer_dirty(bh);
475 brelse(bh);
476}
477
478/* Remove file or directory and it's eas - note that directory must
479 be empty when this is called. */
480
481void hpfs_remove_fnode(struct super_block *s, fnode_secno fno)
482{
483 struct buffer_head *bh;
484 struct fnode *fnode;
485 struct extended_attribute *ea;
486 struct extended_attribute *ea_end;
487 if (!(fnode = hpfs_map_fnode(s, fno, &bh))) return;
488 if (!fnode_is_dir(p: fnode)) hpfs_remove_btree(s, btree: &fnode->btree);
489 else hpfs_remove_dtree(s, le32_to_cpu(fnode->u.external[0].disk_secno));
490 ea_end = fnode_end_ea(fnode);
491 for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
492 if (ea_indirect(ea))
493 hpfs_ea_remove(s, a: ea_sec(ea), ano: ea_in_anode(ea), len: ea_len(ea));
494 hpfs_ea_ext_remove(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(p: fnode), le32_to_cpu(fnode->ea_size_l));
495 brelse(bh);
496 hpfs_free_sectors(s, fno, 1);
497}
498

source code of linux/fs/hpfs/anode.c