File: /usr/src/linux/fs/hpfs/anode.c
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 struct anode *new_anode;
165 if (s->s_hpfs_chk)
166 if (hpfs_stop_cycles(s, up, &c1, &c2, "hpfs_add_sector_to_btree #2")) return -1;
167 if (up != node || !fnod) {
168 if (!(anode = hpfs_map_anode(s, up, &bh))) return -1;
169 btree = &anode->btree;
170 } else {
171 if (!(fnode = hpfs_map_fnode(s, up, &bh))) return -1;
172 btree = &fnode->btree;
173 }
174 if (btree->n_free_nodes) {
175 btree->n_free_nodes--; n = btree->n_used_nodes++;
176 btree->first_free += 8;
177 btree->u.internal[n].file_secno = -1;
178 btree->u.internal[n].down = na;
179 btree->u.internal[n-1].file_secno = fs;
180 mark_buffer_dirty(bh);
181 brelse(bh);
182 brelse(bh2);
183 hpfs_free_sectors(s, ra, 1);
184 if ((anode = hpfs_map_anode(s, na, &bh))) {
185 anode->up = up;
186 anode->btree.fnode_parent = up == node && fnod;
187 mark_buffer_dirty(bh);
188 brelse(bh);
189 }
190 return se;
191 }
192 up = up != node ? anode->up : -1;
193 btree->u.internal[btree->n_used_nodes - 1].file_secno = /*fs*/-1;
194 if (up == -1) anode->up = ra;
195 mark_buffer_dirty(bh);
196 brelse(bh);
197 a = na;
198 if ((new_anode = hpfs_alloc_anode(s, a, &na, &bh))) {
199 anode = new_anode;
200 /*anode->up = up != -1 ? up : ra;*/
201 anode->btree.internal = 1;
202 anode->btree.n_used_nodes = 1;
203 anode->btree.n_free_nodes = 59;
204 anode->btree.first_free = 16;
205 anode->btree.u.internal[0].down = a;
206 anode->btree.u.internal[0].file_secno = -1;
207 mark_buffer_dirty(bh);
208 brelse(bh);
209 if ((anode = hpfs_map_anode(s, a, &bh))) {
210 anode->up = na;
211 mark_buffer_dirty(bh);
212 brelse(bh);
213 }
214 } else na = a;
215 }
216 if ((anode = hpfs_map_anode(s, na, &bh))) {
217 anode->up = node;
218 if (fnod) anode->btree.fnode_parent = 1;
219 mark_buffer_dirty(bh);
220 brelse(bh);
221 }
222 if (!fnod) {
223 if (!(anode = hpfs_map_anode(s, node, &bh))) {
224 brelse(bh2);
225 return -1;
226 }
227 btree = &anode->btree;
228 } else {
229 if (!(fnode = hpfs_map_fnode(s, node, &bh))) {
230 brelse(bh2);
231 return -1;
232 }
233 btree = &fnode->btree;
234 }
235 ranode->up = node;
236 memcpy(&ranode->btree, btree, btree->first_free);
237 if (fnod) ranode->btree.fnode_parent = 1;
238 ranode->btree.n_free_nodes = (ranode->btree.internal ? 60 : 40) - ranode->btree.n_used_nodes;
239 if (ranode->btree.internal) for (n = 0; n < ranode->btree.n_used_nodes; n++) {
240 struct anode *unode;
241 if ((unode = hpfs_map_anode(s, ranode->u.internal[n].down, &bh1))) {
242 unode->up = ra;
243 unode->btree.fnode_parent = 0;
244 mark_buffer_dirty(bh1);
245 brelse(bh1);
246 }
247 }
248 btree->internal = 1;
249 btree->n_free_nodes = fnod ? 10 : 58;
250 btree->n_used_nodes = 2;
251 btree->first_free = (char *)&btree->u.internal[2] - (char *)btree;
252 btree->u.internal[0].file_secno = fs;
253 btree->u.internal[0].down = ra;
254 btree->u.internal[1].file_secno = -1;
255 btree->u.internal[1].down = na;
256 mark_buffer_dirty(bh);
257 brelse(bh);
258 mark_buffer_dirty(bh2);
259 brelse(bh2);
260 return se;
261 }
262
263 /*
264 * Remove allocation tree. Recursion would look much nicer but
265 * I want to avoid it because it can cause stack overflow.
266 */
267
268 void hpfs_remove_btree(struct super_block *s, struct bplus_header *btree)
269 {
270 struct bplus_header *btree1 = btree;
271 struct anode *anode = NULL;
272 anode_secno ano = 0, oano;
273 struct buffer_head *bh;
274 int level = 0;
275 int pos = 0;
276 int i;
277 int c1, c2 = 0;
278 int d1, d2;
279 go_down:
280 d2 = 0;
281 while (btree1->internal) {
282 ano = btree1->u.internal[pos].down;
283 if (level) brelse(bh);
284 if (s->s_hpfs_chk)
285 if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1"))
286 return;
287 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
288 btree1 = &anode->btree;
289 level++;
290 pos = 0;
291 }
292 for (i = 0; i < btree1->n_used_nodes; i++)
293 hpfs_free_sectors(s, btree1->u.external[i].disk_secno, btree1->u.external[i].length);
294 go_up:
295 if (!level) return;
296 brelse(bh);
297 if (s->s_hpfs_chk)
298 if (hpfs_stop_cycles(s, ano, &c1, &c2, "hpfs_remove_btree #2")) return;
299 hpfs_free_sectors(s, ano, 1);
300 oano = ano;
301 ano = anode->up;
302 if (--level) {
303 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
304 btree1 = &anode->btree;
305 } else btree1 = btree;
306 for (i = 0; i < btree1->n_used_nodes; i++) {
307 if (btree1->u.internal[i].down == oano) {
308 if ((pos = i + 1) < btree1->n_used_nodes)
309 goto go_down;
310 else
311 goto go_up;
312 }
313 }
314 hpfs_error(s,
315 "reference to anode %08x not found in anode %08x "
316 "(probably bad up pointer)",
317 oano, level ? ano : -1);
318 if (level)
319 brelse(bh);
320 }
321
322 /* Just a wrapper around hpfs_bplus_lookup .. used for reading eas */
323
324 static secno anode_lookup(struct super_block *s, anode_secno a, unsigned sec)
325 {
326 struct anode *anode;
327 struct buffer_head *bh;
328 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
329 return hpfs_bplus_lookup(s, NULL, &anode->btree, sec, bh);
330 }
331
332 int hpfs_ea_read(struct super_block *s, secno a, int ano, unsigned pos,
333 unsigned len, char *buf)
334 {
335 struct buffer_head *bh;
336 char *data;
337 secno sec;
338 unsigned l;
339 while (len) {
340 if (ano) {
341 if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
342 return -1;
343 } else sec = a + (pos >> 9);
344 if (s->s_hpfs_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #1")) return -1;
345 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
346 return -1;
347 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
348 memcpy(buf, data + (pos & 0x1ff), l);
349 brelse(bh);
350 buf += l; pos += l; len -= l;
351 }
352 return 0;
353 }
354
355 int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos,
356 unsigned len, char *buf)
357 {
358 struct buffer_head *bh;
359 char *data;
360 secno sec;
361 unsigned l;
362 while (len) {
363 if (ano) {
364 if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
365 return -1;
366 } else sec = a + (pos >> 9);
367 if (s->s_hpfs_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #2")) return -1;
368 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
369 return -1;
370 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
371 memcpy(data + (pos & 0x1ff), buf, l);
372 mark_buffer_dirty(bh);
373 brelse(bh);
374 buf += l; pos += l; len -= l;
375 }
376 return 0;
377 }
378
379 void hpfs_ea_remove(struct super_block *s, secno a, int ano, unsigned len)
380 {
381 struct anode *anode;
382 struct buffer_head *bh;
383 if (ano) {
384 if (!(anode = hpfs_map_anode(s, a, &bh))) return;
385 hpfs_remove_btree(s, &anode->btree);
386 brelse(bh);
387 hpfs_free_sectors(s, a, 1);
388 } else hpfs_free_sectors(s, a, (len + 511) >> 9);
389 }
390
391 /* Truncate allocation tree. Doesn't join anodes - I hope it doesn't matter */
392
393 void hpfs_truncate_btree(struct super_block *s, secno f, int fno, unsigned secs)
394 {
395 struct fnode *fnode;
396 struct anode *anode;
397 struct buffer_head *bh;
398 struct bplus_header *btree;
399 anode_secno node = f;
400 int i, j, nodes;
401 int c1, c2 = 0;
402 if (fno) {
403 if (!(fnode = hpfs_map_fnode(s, f, &bh))) return;
404 btree = &fnode->btree;
405 } else {
406 if (!(anode = hpfs_map_anode(s, f, &bh))) return;
407 btree = &anode->btree;
408 }
409 if (!secs) {
410 hpfs_remove_btree(s, btree);
411 if (fno) {
412 btree->n_free_nodes = 8;
413 btree->n_used_nodes = 0;
414 btree->first_free = 8;
415 btree->internal = 0;
416 mark_buffer_dirty(bh);
417 } else hpfs_free_sectors(s, f, 1);
418 brelse(bh);
419 return;
420 }
421 while (btree->internal) {
422 nodes = btree->n_used_nodes + btree->n_free_nodes;
423 for (i = 0; i < btree->n_used_nodes; i++)
424 if (btree->u.internal[i].file_secno >= secs) goto f;
425 brelse(bh);
426 hpfs_error(s, "internal btree %08x doesn't end with -1", node);
427 return;
428 f:
429 for (j = i + 1; j < btree->n_used_nodes; j++)
430 hpfs_ea_remove(s, btree->u.internal[j].down, 1, 0);
431 btree->n_used_nodes = i + 1;
432 btree->n_free_nodes = nodes - btree->n_used_nodes;
433 btree->first_free = 8 + 8 * btree->n_used_nodes;
434 mark_buffer_dirty(bh);
435 if (btree->u.internal[i].file_secno == secs) {
436 brelse(bh);
437 return;
438 }
439 node = btree->u.internal[i].down;
440 brelse(bh);
441 if (s->s_hpfs_chk)
442 if (hpfs_stop_cycles(s, node, &c1, &c2, "hpfs_truncate_btree"))
443 return;
444 if (!(anode = hpfs_map_anode(s, node, &bh))) return;
445 btree = &anode->btree;
446 }
447 nodes = btree->n_used_nodes + btree->n_free_nodes;
448 for (i = 0; i < btree->n_used_nodes; i++)
449 if (btree->u.external[i].file_secno + btree->u.external[i].length >= secs) goto ff;
450 brelse(bh);
451 return;
452 ff:
453 if (secs <= btree->u.external[i].file_secno) {
454 hpfs_error(s, "there is an allocation error in file %08x, sector %08x", f, secs);
455 if (i) i--;
456 }
457 else if (btree->u.external[i].file_secno + btree->u.external[i].length > secs) {
458 hpfs_free_sectors(s, btree->u.external[i].disk_secno + secs -
459 btree->u.external[i].file_secno, btree->u.external[i].length
460 - secs + btree->u.external[i].file_secno); /* I hope gcc optimizes this :-) */
461 btree->u.external[i].length = secs - btree->u.external[i].file_secno;
462 }
463 for (j = i + 1; j < btree->n_used_nodes; j++)
464 hpfs_free_sectors(s, btree->u.external[j].disk_secno, btree->u.external[j].length);
465 btree->n_used_nodes = i + 1;
466 btree->n_free_nodes = nodes - btree->n_used_nodes;
467 btree->first_free = 8 + 12 * btree->n_used_nodes;
468 mark_buffer_dirty(bh);
469 brelse(bh);
470 }
471
472 /* Remove file or directory and it's eas - note that directory must
473 be empty when this is called. */
474
475 void hpfs_remove_fnode(struct super_block *s, fnode_secno fno)
476 {
477 struct buffer_head *bh;
478 struct fnode *fnode;
479 struct extended_attribute *ea;
480 struct extended_attribute *ea_end;
481 if (!(fnode = hpfs_map_fnode(s, fno, &bh))) return;
482 if (!fnode->dirflag) hpfs_remove_btree(s, &fnode->btree);
483 else hpfs_remove_dtree(s, fnode->u.external[0].disk_secno);
484 ea_end = fnode_end_ea(fnode);
485 for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
486 if (ea->indirect)
487 hpfs_ea_remove(s, ea_sec(ea), ea->anode, ea_len(ea));
488 hpfs_ea_ext_remove(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l);
489 brelse(bh);
490 hpfs_free_sectors(s, fno, 1);
491 }
492