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
hpfs_bplus_lookup(struct super_block * s,struct inode * inode,struct bplus_header * btree,unsigned sec,struct buffer_head * bh)14 secno 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(s)->sb_chk) if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_bplus_lookup")) return -1;
24 if (bp_internal(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 = GET_BTREE_PTR(&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(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
hpfs_add_sector_to_btree(struct super_block * s,secno node,int fnod,unsigned fsecno)61 secno 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
73 if (fnod) {
74 if (!(fnode = hpfs_map_fnode(s, node, &bh))) return -1;
75 btree = GET_BTREE_PTR(&fnode->btree);
76 } else {
77 if (!(anode = hpfs_map_anode(s, node, &bh))) return -1;
78 btree = GET_BTREE_PTR(&anode->btree);
79 }
80 a = node;
81 go_down:
82 if ((n = btree->n_used_nodes - 1) < -!!fnod) {
83 hpfs_error(s, "anode %08x has no entries", a);
84 brelse(bh);
85 return -1;
86 }
87 if (bp_internal(btree)) {
88 a = le32_to_cpu(btree->u.internal[n].down);
89 btree->u.internal[n].file_secno = cpu_to_le32(-1);
90 mark_buffer_dirty(bh);
91 brelse(bh);
92 if (hpfs_sb(s)->sb_chk)
93 if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_add_sector_to_btree #1")) return -1;
94 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
95 btree = GET_BTREE_PTR(&anode->btree);
96 goto go_down;
97 }
98 if (n >= 0) {
99 if (le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length) != fsecno) {
100 hpfs_error(s, "allocated size %08x, trying to add sector %08x, %cnode %08x",
101 le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length), fsecno,
102 fnod?'f':'a', node);
103 brelse(bh);
104 return -1;
105 }
106 if (hpfs_alloc_if_possible(s, se = le32_to_cpu(btree->u.external[n].disk_secno) + le32_to_cpu(btree->u.external[n].length))) {
107 le32_add_cpu(&btree->u.external[n].length, 1);
108 mark_buffer_dirty(bh);
109 brelse(bh);
110 return se;
111 }
112 } else {
113 if (fsecno) {
114 hpfs_error(s, "empty file %08x, trying to add sector %08x", node, fsecno);
115 brelse(bh);
116 return -1;
117 }
118 se = !fnod ? node : (node + 16384) & ~16383;
119 }
120 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))) {
121 brelse(bh);
122 return -1;
123 }
124 fs = n < 0 ? 0 : le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length);
125 if (!btree->n_free_nodes) {
126 up = a != node ? le32_to_cpu(anode->up) : -1;
127 if (!(anode = hpfs_alloc_anode(s, a, &na, &bh1))) {
128 brelse(bh);
129 hpfs_free_sectors(s, se, 1);
130 return -1;
131 }
132 if (a == node && fnod) {
133 anode->up = cpu_to_le32(node);
134 anode->btree.flags |= BP_fnode_parent;
135 anode->btree.n_used_nodes = btree->n_used_nodes;
136 anode->btree.first_free = btree->first_free;
137 anode->btree.n_free_nodes = 40 - anode->btree.n_used_nodes;
138 memcpy(&anode->u, &btree->u, btree->n_used_nodes * 12);
139 btree->flags |= BP_internal;
140 btree->n_free_nodes = 11;
141 btree->n_used_nodes = 1;
142 btree->first_free = cpu_to_le16((char *)&(btree->u.internal[1]) - (char *)btree);
143 btree->u.internal[0].file_secno = cpu_to_le32(-1);
144 btree->u.internal[0].down = cpu_to_le32(na);
145 mark_buffer_dirty(bh);
146 } else if (!(ranode = hpfs_alloc_anode(s, /*a*/0, &ra, &bh2))) {
147 brelse(bh);
148 brelse(bh1);
149 hpfs_free_sectors(s, se, 1);
150 hpfs_free_sectors(s, na, 1);
151 return -1;
152 }
153 brelse(bh);
154 bh = bh1;
155 btree = GET_BTREE_PTR(&anode->btree);
156 }
157 btree->n_free_nodes--; n = btree->n_used_nodes++;
158 le16_add_cpu(&btree->first_free, 12);
159 btree->u.external[n].disk_secno = cpu_to_le32(se);
160 btree->u.external[n].file_secno = cpu_to_le32(fs);
161 btree->u.external[n].length = cpu_to_le32(1);
162 mark_buffer_dirty(bh);
163 brelse(bh);
164 if ((a == node && fnod) || na == -1) return se;
165 c2 = 0;
166 while (up != (anode_secno)-1) {
167 struct anode *new_anode;
168 if (hpfs_sb(s)->sb_chk)
169 if (hpfs_stop_cycles(s, up, &c1, &c2, "hpfs_add_sector_to_btree #2")) return -1;
170 if (up != node || !fnod) {
171 if (!(anode = hpfs_map_anode(s, up, &bh))) return -1;
172 btree = GET_BTREE_PTR(&anode->btree);
173 } else {
174 if (!(fnode = hpfs_map_fnode(s, up, &bh))) return -1;
175 btree = GET_BTREE_PTR(&fnode->btree);
176 }
177 if (btree->n_free_nodes) {
178 btree->n_free_nodes--; n = btree->n_used_nodes++;
179 le16_add_cpu(&btree->first_free, 8);
180 btree->u.internal[n].file_secno = cpu_to_le32(-1);
181 btree->u.internal[n].down = cpu_to_le32(na);
182 btree->u.internal[n-1].file_secno = cpu_to_le32(fs);
183 mark_buffer_dirty(bh);
184 brelse(bh);
185 brelse(bh2);
186 hpfs_free_sectors(s, ra, 1);
187 if ((anode = hpfs_map_anode(s, na, &bh))) {
188 anode->up = cpu_to_le32(up);
189 if (up == node && fnod)
190 anode->btree.flags |= BP_fnode_parent;
191 else
192 anode->btree.flags &= ~BP_fnode_parent;
193 mark_buffer_dirty(bh);
194 brelse(bh);
195 }
196 return se;
197 }
198 up = up != node ? le32_to_cpu(anode->up) : -1;
199 btree->u.internal[btree->n_used_nodes - 1].file_secno = cpu_to_le32(/*fs*/-1);
200 mark_buffer_dirty(bh);
201 brelse(bh);
202 a = na;
203 if ((new_anode = hpfs_alloc_anode(s, a, &na, &bh))) {
204 anode = new_anode;
205 /*anode->up = cpu_to_le32(up != -1 ? up : ra);*/
206 anode->btree.flags |= BP_internal;
207 anode->btree.n_used_nodes = 1;
208 anode->btree.n_free_nodes = 59;
209 anode->btree.first_free = cpu_to_le16(16);
210 GET_BTREE_PTR(&anode->btree)->u.internal[0].down = cpu_to_le32(a);
211 GET_BTREE_PTR(&anode->btree)->u.internal[0].file_secno = cpu_to_le32(-1);
212 mark_buffer_dirty(bh);
213 brelse(bh);
214 if ((anode = hpfs_map_anode(s, a, &bh))) {
215 anode->up = cpu_to_le32(na);
216 mark_buffer_dirty(bh);
217 brelse(bh);
218 }
219 } else na = a;
220 }
221 if ((anode = hpfs_map_anode(s, na, &bh))) {
222 anode->up = cpu_to_le32(node);
223 if (fnod)
224 anode->btree.flags |= BP_fnode_parent;
225 mark_buffer_dirty(bh);
226 brelse(bh);
227 }
228 if (!fnod) {
229 if (!(anode = hpfs_map_anode(s, node, &bh))) {
230 brelse(bh2);
231 return -1;
232 }
233 btree = GET_BTREE_PTR(&anode->btree);
234 } else {
235 if (!(fnode = hpfs_map_fnode(s, node, &bh))) {
236 brelse(bh2);
237 return -1;
238 }
239 btree = GET_BTREE_PTR(&fnode->btree);
240 }
241 ranode->up = cpu_to_le32(node);
242 memcpy(&ranode->btree, btree, le16_to_cpu(btree->first_free));
243 if (fnod)
244 ranode->btree.flags |= BP_fnode_parent;
245 GET_BTREE_PTR(&ranode->btree)->n_free_nodes = (bp_internal(GET_BTREE_PTR(&ranode->btree)) ? 60 : 40) - GET_BTREE_PTR(&ranode->btree)->n_used_nodes;
246 if (bp_internal(GET_BTREE_PTR(&ranode->btree))) for (n = 0; n < GET_BTREE_PTR(&ranode->btree)->n_used_nodes; n++) {
247 struct anode *unode;
248 if ((unode = hpfs_map_anode(s, le32_to_cpu(ranode->u.internal[n].down), &bh1))) {
249 unode->up = cpu_to_le32(ra);
250 unode->btree.flags &= ~BP_fnode_parent;
251 mark_buffer_dirty(bh1);
252 brelse(bh1);
253 }
254 }
255 btree->flags |= BP_internal;
256 btree->n_free_nodes = fnod ? 10 : 58;
257 btree->n_used_nodes = 2;
258 btree->first_free = cpu_to_le16((char *)&btree->u.internal[2] - (char *)btree);
259 btree->u.internal[0].file_secno = cpu_to_le32(fs);
260 btree->u.internal[0].down = cpu_to_le32(ra);
261 btree->u.internal[1].file_secno = cpu_to_le32(-1);
262 btree->u.internal[1].down = cpu_to_le32(na);
263 mark_buffer_dirty(bh);
264 brelse(bh);
265 mark_buffer_dirty(bh2);
266 brelse(bh2);
267 return se;
268 }
269
270 /*
271 * Remove allocation tree. Recursion would look much nicer but
272 * I want to avoid it because it can cause stack overflow.
273 */
274
hpfs_remove_btree(struct super_block * s,struct bplus_header * btree)275 void hpfs_remove_btree(struct super_block *s, struct bplus_header *btree)
276 {
277 struct bplus_header *btree1 = btree;
278 struct anode *anode = NULL;
279 anode_secno ano = 0, oano;
280 struct buffer_head *bh;
281 int level = 0;
282 int pos = 0;
283 int i;
284 int c1, c2 = 0;
285 int d1, d2;
286 go_down:
287 d2 = 0;
288 while (bp_internal(btree1)) {
289 ano = le32_to_cpu(btree1->u.internal[pos].down);
290 if (level) brelse(bh);
291 if (hpfs_sb(s)->sb_chk)
292 if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1"))
293 return;
294 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
295 btree1 = GET_BTREE_PTR(&anode->btree);
296 level++;
297 pos = 0;
298 }
299 for (i = 0; i < btree1->n_used_nodes; i++)
300 hpfs_free_sectors(s, le32_to_cpu(btree1->u.external[i].disk_secno), le32_to_cpu(btree1->u.external[i].length));
301 go_up:
302 if (!level) return;
303 brelse(bh);
304 if (hpfs_sb(s)->sb_chk)
305 if (hpfs_stop_cycles(s, ano, &c1, &c2, "hpfs_remove_btree #2")) return;
306 hpfs_free_sectors(s, ano, 1);
307 oano = ano;
308 ano = le32_to_cpu(anode->up);
309 if (--level) {
310 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
311 btree1 = GET_BTREE_PTR(&anode->btree);
312 } else btree1 = btree;
313 for (i = 0; i < btree1->n_used_nodes; i++) {
314 if (le32_to_cpu(btree1->u.internal[i].down) == oano) {
315 if ((pos = i + 1) < btree1->n_used_nodes)
316 goto go_down;
317 else
318 goto go_up;
319 }
320 }
321 hpfs_error(s,
322 "reference to anode %08x not found in anode %08x "
323 "(probably bad up pointer)",
324 oano, level ? ano : -1);
325 if (level)
326 brelse(bh);
327 }
328
329 /* Just a wrapper around hpfs_bplus_lookup .. used for reading eas */
330
anode_lookup(struct super_block * s,anode_secno a,unsigned sec)331 static secno anode_lookup(struct super_block *s, anode_secno a, unsigned sec)
332 {
333 struct anode *anode;
334 struct buffer_head *bh;
335 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
336 return hpfs_bplus_lookup(s, NULL, GET_BTREE_PTR(&anode->btree), sec, bh);
337 }
338
hpfs_ea_read(struct super_block * s,secno a,int ano,unsigned pos,unsigned len,char * buf)339 int hpfs_ea_read(struct super_block *s, secno a, int ano, unsigned pos,
340 unsigned len, char *buf)
341 {
342 struct buffer_head *bh;
343 char *data;
344 secno sec;
345 unsigned l;
346 while (len) {
347 if (ano) {
348 if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
349 return -1;
350 } else sec = a + (pos >> 9);
351 if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #1")) return -1;
352 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
353 return -1;
354 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
355 memcpy(buf, data + (pos & 0x1ff), l);
356 brelse(bh);
357 buf += l; pos += l; len -= l;
358 }
359 return 0;
360 }
361
hpfs_ea_write(struct super_block * s,secno a,int ano,unsigned pos,unsigned len,const char * buf)362 int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos,
363 unsigned len, const char *buf)
364 {
365 struct buffer_head *bh;
366 char *data;
367 secno sec;
368 unsigned l;
369 while (len) {
370 if (ano) {
371 if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
372 return -1;
373 } else sec = a + (pos >> 9);
374 if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #2")) return -1;
375 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
376 return -1;
377 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
378 memcpy(data + (pos & 0x1ff), buf, l);
379 mark_buffer_dirty(bh);
380 brelse(bh);
381 buf += l; pos += l; len -= l;
382 }
383 return 0;
384 }
385
hpfs_ea_remove(struct super_block * s,secno a,int ano,unsigned len)386 void hpfs_ea_remove(struct super_block *s, secno a, int ano, unsigned len)
387 {
388 struct anode *anode;
389 struct buffer_head *bh;
390 if (ano) {
391 if (!(anode = hpfs_map_anode(s, a, &bh))) return;
392 hpfs_remove_btree(s, GET_BTREE_PTR(&anode->btree));
393 brelse(bh);
394 hpfs_free_sectors(s, a, 1);
395 } else hpfs_free_sectors(s, a, (len + 511) >> 9);
396 }
397
398 /* Truncate allocation tree. Doesn't join anodes - I hope it doesn't matter */
399
hpfs_truncate_btree(struct super_block * s,secno f,int fno,unsigned secs)400 void hpfs_truncate_btree(struct super_block *s, secno f, int fno, unsigned secs)
401 {
402 struct fnode *fnode;
403 struct anode *anode;
404 struct buffer_head *bh;
405 struct bplus_header *btree;
406 anode_secno node = f;
407 int i, j, nodes;
408 int c1, c2 = 0;
409 if (fno) {
410 if (!(fnode = hpfs_map_fnode(s, f, &bh))) return;
411 btree = GET_BTREE_PTR(&fnode->btree);
412 } else {
413 if (!(anode = hpfs_map_anode(s, f, &bh))) return;
414 btree = GET_BTREE_PTR(&anode->btree);
415 }
416 if (!secs) {
417 hpfs_remove_btree(s, btree);
418 if (fno) {
419 btree->n_free_nodes = 8;
420 btree->n_used_nodes = 0;
421 btree->first_free = cpu_to_le16(8);
422 btree->flags &= ~BP_internal;
423 mark_buffer_dirty(bh);
424 } else hpfs_free_sectors(s, f, 1);
425 brelse(bh);
426 return;
427 }
428 while (bp_internal(btree)) {
429 nodes = btree->n_used_nodes + btree->n_free_nodes;
430 for (i = 0; i < btree->n_used_nodes; i++)
431 if (le32_to_cpu(btree->u.internal[i].file_secno) >= secs) goto f;
432 brelse(bh);
433 hpfs_error(s, "internal btree %08x doesn't end with -1", node);
434 return;
435 f:
436 for (j = i + 1; j < btree->n_used_nodes; j++)
437 hpfs_ea_remove(s, le32_to_cpu(btree->u.internal[j].down), 1, 0);
438 btree->n_used_nodes = i + 1;
439 btree->n_free_nodes = nodes - btree->n_used_nodes;
440 btree->first_free = cpu_to_le16(8 + 8 * btree->n_used_nodes);
441 mark_buffer_dirty(bh);
442 if (btree->u.internal[i].file_secno == cpu_to_le32(secs)) {
443 brelse(bh);
444 return;
445 }
446 node = le32_to_cpu(btree->u.internal[i].down);
447 brelse(bh);
448 if (hpfs_sb(s)->sb_chk)
449 if (hpfs_stop_cycles(s, node, &c1, &c2, "hpfs_truncate_btree"))
450 return;
451 if (!(anode = hpfs_map_anode(s, node, &bh))) return;
452 btree = GET_BTREE_PTR(&anode->btree);
453 }
454 nodes = btree->n_used_nodes + btree->n_free_nodes;
455 for (i = 0; i < btree->n_used_nodes; i++)
456 if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) >= secs) goto ff;
457 brelse(bh);
458 return;
459 ff:
460 if (secs <= le32_to_cpu(btree->u.external[i].file_secno)) {
461 hpfs_error(s, "there is an allocation error in file %08x, sector %08x", f, secs);
462 if (i) i--;
463 }
464 else if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > secs) {
465 hpfs_free_sectors(s, le32_to_cpu(btree->u.external[i].disk_secno) + secs -
466 le32_to_cpu(btree->u.external[i].file_secno), le32_to_cpu(btree->u.external[i].length)
467 - secs + le32_to_cpu(btree->u.external[i].file_secno)); /* I hope gcc optimizes this :-) */
468 btree->u.external[i].length = cpu_to_le32(secs - le32_to_cpu(btree->u.external[i].file_secno));
469 }
470 for (j = i + 1; j < btree->n_used_nodes; j++)
471 hpfs_free_sectors(s, le32_to_cpu(btree->u.external[j].disk_secno), le32_to_cpu(btree->u.external[j].length));
472 btree->n_used_nodes = i + 1;
473 btree->n_free_nodes = nodes - btree->n_used_nodes;
474 btree->first_free = cpu_to_le16(8 + 12 * btree->n_used_nodes);
475 mark_buffer_dirty(bh);
476 brelse(bh);
477 }
478
479 /* Remove file or directory and it's eas - note that directory must
480 be empty when this is called. */
481
hpfs_remove_fnode(struct super_block * s,fnode_secno fno)482 void hpfs_remove_fnode(struct super_block *s, fnode_secno fno)
483 {
484 struct buffer_head *bh;
485 struct fnode *fnode;
486 struct extended_attribute *ea;
487 struct extended_attribute *ea_end;
488 if (!(fnode = hpfs_map_fnode(s, fno, &bh))) return;
489 if (!fnode_is_dir(fnode)) hpfs_remove_btree(s, GET_BTREE_PTR(&fnode->btree));
490 else hpfs_remove_dtree(s, le32_to_cpu(fnode->u.external[0].disk_secno));
491 ea_end = fnode_end_ea(fnode);
492 for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
493 if (ea_indirect(ea))
494 hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
495 hpfs_ea_ext_remove(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l));
496 brelse(bh);
497 hpfs_free_sectors(s, fno, 1);
498 }
499