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