anode.c

  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(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
 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
 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
275void 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
331static 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
339int 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
362int 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
386void 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
400void 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
482void 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}