1/*
2 *  linux/fs/hpfs/dnode.c
3 *
4 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5 *
6 *  handling directory dnode tree - adding, deleteing & searching for dirents
7 */
8
9#include "hpfs_fn.h"
10
11static loff_t get_pos(struct dnode *d, struct hpfs_dirent *fde)
12{
13	struct hpfs_dirent *de;
14	struct hpfs_dirent *de_end = dnode_end_de(d);
15	int i = 1;
16	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
17		if (de == fde) return ((loff_t) le32_to_cpu(d->self) << 4) | (loff_t)i;
18		i++;
19	}
20	pr_info("%s(): not_found\n", __func__);
21	return ((loff_t)le32_to_cpu(d->self) << 4) | (loff_t)1;
22}
23
24void hpfs_add_pos(struct inode *inode, loff_t *pos)
25{
26	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
27	int i = 0;
28	loff_t **ppos;
29
30	if (hpfs_inode->i_rddir_off)
31		for (; hpfs_inode->i_rddir_off[i]; i++)
32			if (hpfs_inode->i_rddir_off[i] == pos) return;
33	if (!(i&0x0f)) {
34		if (!(ppos = kmalloc((i+0x11) * sizeof(loff_t*), GFP_NOFS))) {
35			pr_err("out of memory for position list\n");
36			return;
37		}
38		if (hpfs_inode->i_rddir_off) {
39			memcpy(ppos, hpfs_inode->i_rddir_off, i * sizeof(loff_t));
40			kfree(hpfs_inode->i_rddir_off);
41		}
42		hpfs_inode->i_rddir_off = ppos;
43	}
44	hpfs_inode->i_rddir_off[i] = pos;
45	hpfs_inode->i_rddir_off[i + 1] = NULL;
46}
47
48void hpfs_del_pos(struct inode *inode, loff_t *pos)
49{
50	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
51	loff_t **i, **j;
52
53	if (!hpfs_inode->i_rddir_off) goto not_f;
54	for (i = hpfs_inode->i_rddir_off; *i; i++) if (*i == pos) goto fnd;
55	goto not_f;
56	fnd:
57	for (j = i + 1; *j; j++) ;
58	*i = *(j - 1);
59	*(j - 1) = NULL;
60	if (j - 1 == hpfs_inode->i_rddir_off) {
61		kfree(hpfs_inode->i_rddir_off);
62		hpfs_inode->i_rddir_off = NULL;
63	}
64	return;
65	not_f:
66	/*pr_warn("position pointer %p->%08x not found\n",
67		  pos, (int)*pos);*/
68	return;
69}
70
71static void for_all_poss(struct inode *inode, void (*f)(loff_t *, loff_t, loff_t),
72			 loff_t p1, loff_t p2)
73{
74	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
75	loff_t **i;
76
77	if (!hpfs_inode->i_rddir_off) return;
78	for (i = hpfs_inode->i_rddir_off; *i; i++) (*f)(*i, p1, p2);
79	return;
80}
81
82static void hpfs_pos_subst(loff_t *p, loff_t f, loff_t t)
83{
84	if (*p == f) *p = t;
85}
86
87/*void hpfs_hpfs_pos_substd(loff_t *p, loff_t f, loff_t t)
88{
89	if ((*p & ~0x3f) == (f & ~0x3f)) *p = (t & ~0x3f) | (*p & 0x3f);
90}*/
91
92static void hpfs_pos_ins(loff_t *p, loff_t d, loff_t c)
93{
94	if ((*p & ~0x3f) == (d & ~0x3f) && (*p & 0x3f) >= (d & 0x3f)) {
95		int n = (*p & 0x3f) + c;
96		if (n > 0x3f)
97			pr_err("%s(): %08x + %d\n",
98				__func__, (int)*p, (int)c >> 8);
99		else
100			*p = (*p & ~0x3f) | n;
101	}
102}
103
104static void hpfs_pos_del(loff_t *p, loff_t d, loff_t c)
105{
106	if ((*p & ~0x3f) == (d & ~0x3f) && (*p & 0x3f) >= (d & 0x3f)) {
107		int n = (*p & 0x3f) - c;
108		if (n < 1)
109			pr_err("%s(): %08x - %d\n",
110				__func__, (int)*p, (int)c >> 8);
111		else
112			*p = (*p & ~0x3f) | n;
113	}
114}
115
116static struct hpfs_dirent *dnode_pre_last_de(struct dnode *d)
117{
118	struct hpfs_dirent *de, *de_end, *dee = NULL, *deee = NULL;
119	de_end = dnode_end_de(d);
120	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
121		deee = dee; dee = de;
122	}
123	return deee;
124}
125
126static struct hpfs_dirent *dnode_last_de(struct dnode *d)
127{
128	struct hpfs_dirent *de, *de_end, *dee = NULL;
129	de_end = dnode_end_de(d);
130	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
131		dee = de;
132	}
133	return dee;
134}
135
136static void set_last_pointer(struct super_block *s, struct dnode *d, dnode_secno ptr)
137{
138	struct hpfs_dirent *de;
139	if (!(de = dnode_last_de(d))) {
140		hpfs_error(s, "set_last_pointer: empty dnode %08x", le32_to_cpu(d->self));
141		return;
142	}
143	if (hpfs_sb(s)->sb_chk) {
144		if (de->down) {
145			hpfs_error(s, "set_last_pointer: dnode %08x has already last pointer %08x",
146				le32_to_cpu(d->self), de_down_pointer(de));
147			return;
148		}
149		if (le16_to_cpu(de->length) != 32) {
150			hpfs_error(s, "set_last_pointer: bad last dirent in dnode %08x", le32_to_cpu(d->self));
151			return;
152		}
153	}
154	if (ptr) {
155		le32_add_cpu(&d->first_free, 4);
156		if (le32_to_cpu(d->first_free) > 2048) {
157			hpfs_error(s, "set_last_pointer: too long dnode %08x", le32_to_cpu(d->self));
158			le32_add_cpu(&d->first_free, -4);
159			return;
160		}
161		de->length = cpu_to_le16(36);
162		de->down = 1;
163		*(__le32 *)((char *)de + 32) = cpu_to_le32(ptr);
164	}
165}
166
167/* Add an entry to dnode and don't care if it grows over 2048 bytes */
168
169struct hpfs_dirent *hpfs_add_de(struct super_block *s, struct dnode *d,
170				const unsigned char *name,
171				unsigned namelen, secno down_ptr)
172{
173	struct hpfs_dirent *de;
174	struct hpfs_dirent *de_end = dnode_end_de(d);
175	unsigned d_size = de_size(namelen, down_ptr);
176	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
177		int c = hpfs_compare_names(s, name, namelen, de->name, de->namelen, de->last);
178		if (!c) {
179			hpfs_error(s, "name (%c,%d) already exists in dnode %08x", *name, namelen, le32_to_cpu(d->self));
180			return NULL;
181		}
182		if (c < 0) break;
183	}
184	memmove((char *)de + d_size, de, (char *)de_end - (char *)de);
185	memset(de, 0, d_size);
186	if (down_ptr) {
187		*(__le32 *)((char *)de + d_size - 4) = cpu_to_le32(down_ptr);
188		de->down = 1;
189	}
190	de->length = cpu_to_le16(d_size);
191	de->not_8x3 = hpfs_is_name_long(name, namelen);
192	de->namelen = namelen;
193	memcpy(de->name, name, namelen);
194	le32_add_cpu(&d->first_free, d_size);
195	return de;
196}
197
198/* Delete dirent and don't care about its subtree */
199
200static void hpfs_delete_de(struct super_block *s, struct dnode *d,
201			   struct hpfs_dirent *de)
202{
203	if (de->last) {
204		hpfs_error(s, "attempt to delete last dirent in dnode %08x", le32_to_cpu(d->self));
205		return;
206	}
207	d->first_free = cpu_to_le32(le32_to_cpu(d->first_free) - le16_to_cpu(de->length));
208	memmove(de, de_next_de(de), le32_to_cpu(d->first_free) + (char *)d - (char *)de);
209}
210
211static void fix_up_ptrs(struct super_block *s, struct dnode *d)
212{
213	struct hpfs_dirent *de;
214	struct hpfs_dirent *de_end = dnode_end_de(d);
215	dnode_secno dno = le32_to_cpu(d->self);
216	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de))
217		if (de->down) {
218			struct quad_buffer_head qbh;
219			struct dnode *dd;
220			if ((dd = hpfs_map_dnode(s, de_down_pointer(de), &qbh))) {
221				if (le32_to_cpu(dd->up) != dno || dd->root_dnode) {
222					dd->up = cpu_to_le32(dno);
223					dd->root_dnode = 0;
224					hpfs_mark_4buffers_dirty(&qbh);
225				}
226				hpfs_brelse4(&qbh);
227			}
228		}
229}
230
231/* Add an entry to dnode and do dnode splitting if required */
232
233static int hpfs_add_to_dnode(struct inode *i, dnode_secno dno,
234			     const unsigned char *name, unsigned namelen,
235			     struct hpfs_dirent *new_de, dnode_secno down_ptr)
236{
237	struct quad_buffer_head qbh, qbh1, qbh2;
238	struct dnode *d, *ad, *rd, *nd = NULL;
239	dnode_secno adno, rdno;
240	struct hpfs_dirent *de;
241	struct hpfs_dirent nde;
242	unsigned char *nname;
243	int h;
244	int pos;
245	struct buffer_head *bh;
246	struct fnode *fnode;
247	int c1, c2 = 0;
248	if (!(nname = kmalloc(256, GFP_NOFS))) {
249		pr_err("out of memory, can't add to dnode\n");
250		return 1;
251	}
252	go_up:
253	if (namelen >= 256) {
254		hpfs_error(i->i_sb, "%s(): namelen == %d", __func__, namelen);
255		kfree(nd);
256		kfree(nname);
257		return 1;
258	}
259	if (!(d = hpfs_map_dnode(i->i_sb, dno, &qbh))) {
260		kfree(nd);
261		kfree(nname);
262		return 1;
263	}
264	go_up_a:
265	if (hpfs_sb(i->i_sb)->sb_chk)
266		if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "hpfs_add_to_dnode")) {
267			hpfs_brelse4(&qbh);
268			kfree(nd);
269			kfree(nname);
270			return 1;
271		}
272	if (le32_to_cpu(d->first_free) + de_size(namelen, down_ptr) <= 2048) {
273		loff_t t;
274		copy_de(de=hpfs_add_de(i->i_sb, d, name, namelen, down_ptr), new_de);
275		t = get_pos(d, de);
276		for_all_poss(i, hpfs_pos_ins, t, 1);
277		for_all_poss(i, hpfs_pos_subst, 4, t);
278		for_all_poss(i, hpfs_pos_subst, 5, t + 1);
279		hpfs_mark_4buffers_dirty(&qbh);
280		hpfs_brelse4(&qbh);
281		kfree(nd);
282		kfree(nname);
283		return 0;
284	}
285	if (!nd) if (!(nd = kmalloc(0x924, GFP_NOFS))) {
286		/* 0x924 is a max size of dnode after adding a dirent with
287		   max name length. We alloc this only once. There must
288		   not be any error while splitting dnodes, otherwise the
289		   whole directory, not only file we're adding, would
290		   be lost. */
291		pr_err("out of memory for dnode splitting\n");
292		hpfs_brelse4(&qbh);
293		kfree(nname);
294		return 1;
295	}
296	memcpy(nd, d, le32_to_cpu(d->first_free));
297	copy_de(de = hpfs_add_de(i->i_sb, nd, name, namelen, down_ptr), new_de);
298	for_all_poss(i, hpfs_pos_ins, get_pos(nd, de), 1);
299	h = ((char *)dnode_last_de(nd) - (char *)nd) / 2 + 10;
300	if (!(ad = hpfs_alloc_dnode(i->i_sb, le32_to_cpu(d->up), &adno, &qbh1))) {
301		hpfs_error(i->i_sb, "unable to alloc dnode - dnode tree will be corrupted");
302		hpfs_brelse4(&qbh);
303		kfree(nd);
304		kfree(nname);
305		return 1;
306	}
307	i->i_size += 2048;
308	i->i_blocks += 4;
309	pos = 1;
310	for (de = dnode_first_de(nd); (char *)de_next_de(de) - (char *)nd < h; de = de_next_de(de)) {
311		copy_de(hpfs_add_de(i->i_sb, ad, de->name, de->namelen, de->down ? de_down_pointer(de) : 0), de);
312		for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | pos, ((loff_t)adno << 4) | pos);
313		pos++;
314	}
315	copy_de(new_de = &nde, de);
316	memcpy(nname, de->name, de->namelen);
317	name = nname;
318	namelen = de->namelen;
319	for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | pos, 4);
320	down_ptr = adno;
321	set_last_pointer(i->i_sb, ad, de->down ? de_down_pointer(de) : 0);
322	de = de_next_de(de);
323	memmove((char *)nd + 20, de, le32_to_cpu(nd->first_free) + (char *)nd - (char *)de);
324	le32_add_cpu(&nd->first_free, -((char *)de - (char *)nd - 20));
325	memcpy(d, nd, le32_to_cpu(nd->first_free));
326	for_all_poss(i, hpfs_pos_del, (loff_t)dno << 4, pos);
327	fix_up_ptrs(i->i_sb, ad);
328	if (!d->root_dnode) {
329		ad->up = d->up;
330		dno = le32_to_cpu(ad->up);
331		hpfs_mark_4buffers_dirty(&qbh);
332		hpfs_brelse4(&qbh);
333		hpfs_mark_4buffers_dirty(&qbh1);
334		hpfs_brelse4(&qbh1);
335		goto go_up;
336	}
337	if (!(rd = hpfs_alloc_dnode(i->i_sb, le32_to_cpu(d->up), &rdno, &qbh2))) {
338		hpfs_error(i->i_sb, "unable to alloc dnode - dnode tree will be corrupted");
339		hpfs_brelse4(&qbh);
340		hpfs_brelse4(&qbh1);
341		kfree(nd);
342		kfree(nname);
343		return 1;
344	}
345	i->i_size += 2048;
346	i->i_blocks += 4;
347	rd->root_dnode = 1;
348	rd->up = d->up;
349	if (!(fnode = hpfs_map_fnode(i->i_sb, le32_to_cpu(d->up), &bh))) {
350		hpfs_free_dnode(i->i_sb, rdno);
351		hpfs_brelse4(&qbh);
352		hpfs_brelse4(&qbh1);
353		hpfs_brelse4(&qbh2);
354		kfree(nd);
355		kfree(nname);
356		return 1;
357	}
358	fnode->u.external[0].disk_secno = cpu_to_le32(rdno);
359	mark_buffer_dirty(bh);
360	brelse(bh);
361	hpfs_i(i)->i_dno = rdno;
362	d->up = ad->up = cpu_to_le32(rdno);
363	d->root_dnode = ad->root_dnode = 0;
364	hpfs_mark_4buffers_dirty(&qbh);
365	hpfs_brelse4(&qbh);
366	hpfs_mark_4buffers_dirty(&qbh1);
367	hpfs_brelse4(&qbh1);
368	qbh = qbh2;
369	set_last_pointer(i->i_sb, rd, dno);
370	dno = rdno;
371	d = rd;
372	goto go_up_a;
373}
374
375/*
376 * Add an entry to directory btree.
377 * I hate such crazy directory structure.
378 * It's easy to read but terrible to write.
379 * I wrote this directory code 4 times.
380 * I hope, now it's finally bug-free.
381 */
382
383int hpfs_add_dirent(struct inode *i,
384		    const unsigned char *name, unsigned namelen,
385		    struct hpfs_dirent *new_de)
386{
387	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
388	struct dnode *d;
389	struct hpfs_dirent *de, *de_end;
390	struct quad_buffer_head qbh;
391	dnode_secno dno;
392	int c;
393	int c1, c2 = 0;
394	dno = hpfs_inode->i_dno;
395	down:
396	if (hpfs_sb(i->i_sb)->sb_chk)
397		if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "hpfs_add_dirent")) return 1;
398	if (!(d = hpfs_map_dnode(i->i_sb, dno, &qbh))) return 1;
399	de_end = dnode_end_de(d);
400	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
401		if (!(c = hpfs_compare_names(i->i_sb, name, namelen, de->name, de->namelen, de->last))) {
402			hpfs_brelse4(&qbh);
403			return -1;
404		}
405		if (c < 0) {
406			if (de->down) {
407				dno = de_down_pointer(de);
408				hpfs_brelse4(&qbh);
409				goto down;
410			}
411			break;
412		}
413	}
414	hpfs_brelse4(&qbh);
415	if (hpfs_check_free_dnodes(i->i_sb, FREE_DNODES_ADD)) {
416		c = 1;
417		goto ret;
418	}
419	i->i_version++;
420	c = hpfs_add_to_dnode(i, dno, name, namelen, new_de, 0);
421	ret:
422	return c;
423}
424
425/*
426 * Find dirent with higher name in 'from' subtree and move it to 'to' dnode.
427 * Return the dnode we moved from (to be checked later if it's empty)
428 */
429
430static secno move_to_top(struct inode *i, dnode_secno from, dnode_secno to)
431{
432	dnode_secno dno, ddno;
433	dnode_secno chk_up = to;
434	struct dnode *dnode;
435	struct quad_buffer_head qbh;
436	struct hpfs_dirent *de, *nde;
437	int a;
438	loff_t t;
439	int c1, c2 = 0;
440	dno = from;
441	while (1) {
442		if (hpfs_sb(i->i_sb)->sb_chk)
443			if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "move_to_top"))
444				return 0;
445		if (!(dnode = hpfs_map_dnode(i->i_sb, dno, &qbh))) return 0;
446		if (hpfs_sb(i->i_sb)->sb_chk) {
447			if (le32_to_cpu(dnode->up) != chk_up) {
448				hpfs_error(i->i_sb, "move_to_top: up pointer from %08x should be %08x, is %08x",
449					dno, chk_up, le32_to_cpu(dnode->up));
450				hpfs_brelse4(&qbh);
451				return 0;
452			}
453			chk_up = dno;
454		}
455		if (!(de = dnode_last_de(dnode))) {
456			hpfs_error(i->i_sb, "move_to_top: dnode %08x has no last de", dno);
457			hpfs_brelse4(&qbh);
458			return 0;
459		}
460		if (!de->down) break;
461		dno = de_down_pointer(de);
462		hpfs_brelse4(&qbh);
463	}
464	while (!(de = dnode_pre_last_de(dnode))) {
465		dnode_secno up = le32_to_cpu(dnode->up);
466		hpfs_brelse4(&qbh);
467		hpfs_free_dnode(i->i_sb, dno);
468		i->i_size -= 2048;
469		i->i_blocks -= 4;
470		for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | 1, 5);
471		if (up == to) return to;
472		if (!(dnode = hpfs_map_dnode(i->i_sb, up, &qbh))) return 0;
473		if (dnode->root_dnode) {
474			hpfs_error(i->i_sb, "move_to_top: got to root_dnode while moving from %08x to %08x", from, to);
475			hpfs_brelse4(&qbh);
476			return 0;
477		}
478		de = dnode_last_de(dnode);
479		if (!de || !de->down) {
480			hpfs_error(i->i_sb, "move_to_top: dnode %08x doesn't point down to %08x", up, dno);
481			hpfs_brelse4(&qbh);
482			return 0;
483		}
484		le32_add_cpu(&dnode->first_free, -4);
485		le16_add_cpu(&de->length, -4);
486		de->down = 0;
487		hpfs_mark_4buffers_dirty(&qbh);
488		dno = up;
489	}
490	t = get_pos(dnode, de);
491	for_all_poss(i, hpfs_pos_subst, t, 4);
492	for_all_poss(i, hpfs_pos_subst, t + 1, 5);
493	if (!(nde = kmalloc(le16_to_cpu(de->length), GFP_NOFS))) {
494		hpfs_error(i->i_sb, "out of memory for dirent - directory will be corrupted");
495		hpfs_brelse4(&qbh);
496		return 0;
497	}
498	memcpy(nde, de, le16_to_cpu(de->length));
499	ddno = de->down ? de_down_pointer(de) : 0;
500	hpfs_delete_de(i->i_sb, dnode, de);
501	set_last_pointer(i->i_sb, dnode, ddno);
502	hpfs_mark_4buffers_dirty(&qbh);
503	hpfs_brelse4(&qbh);
504	a = hpfs_add_to_dnode(i, to, nde->name, nde->namelen, nde, from);
505	kfree(nde);
506	if (a) return 0;
507	return dno;
508}
509
510/*
511 * Check if a dnode is empty and delete it from the tree
512 * (chkdsk doesn't like empty dnodes)
513 */
514
515static void delete_empty_dnode(struct inode *i, dnode_secno dno)
516{
517	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
518	struct quad_buffer_head qbh;
519	struct dnode *dnode;
520	dnode_secno down, up, ndown;
521	int p;
522	struct hpfs_dirent *de;
523	int c1, c2 = 0;
524	try_it_again:
525	if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "delete_empty_dnode")) return;
526	if (!(dnode = hpfs_map_dnode(i->i_sb, dno, &qbh))) return;
527	if (le32_to_cpu(dnode->first_free) > 56) goto end;
528	if (le32_to_cpu(dnode->first_free) == 52 || le32_to_cpu(dnode->first_free) == 56) {
529		struct hpfs_dirent *de_end;
530		int root = dnode->root_dnode;
531		up = le32_to_cpu(dnode->up);
532		de = dnode_first_de(dnode);
533		down = de->down ? de_down_pointer(de) : 0;
534		if (hpfs_sb(i->i_sb)->sb_chk) if (root && !down) {
535			hpfs_error(i->i_sb, "delete_empty_dnode: root dnode %08x is empty", dno);
536			goto end;
537		}
538		hpfs_brelse4(&qbh);
539		hpfs_free_dnode(i->i_sb, dno);
540		i->i_size -= 2048;
541		i->i_blocks -= 4;
542		if (root) {
543			struct fnode *fnode;
544			struct buffer_head *bh;
545			struct dnode *d1;
546			struct quad_buffer_head qbh1;
547			if (hpfs_sb(i->i_sb)->sb_chk)
548				if (up != i->i_ino) {
549					hpfs_error(i->i_sb,
550						   "bad pointer to fnode, dnode %08x, pointing to %08x, should be %08lx",
551						   dno, up,
552						   (unsigned long)i->i_ino);
553					return;
554				}
555			if ((d1 = hpfs_map_dnode(i->i_sb, down, &qbh1))) {
556				d1->up = cpu_to_le32(up);
557				d1->root_dnode = 1;
558				hpfs_mark_4buffers_dirty(&qbh1);
559				hpfs_brelse4(&qbh1);
560			}
561			if ((fnode = hpfs_map_fnode(i->i_sb, up, &bh))) {
562				fnode->u.external[0].disk_secno = cpu_to_le32(down);
563				mark_buffer_dirty(bh);
564				brelse(bh);
565			}
566			hpfs_inode->i_dno = down;
567			for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | 1, (loff_t) 12);
568			return;
569		}
570		if (!(dnode = hpfs_map_dnode(i->i_sb, up, &qbh))) return;
571		p = 1;
572		de_end = dnode_end_de(dnode);
573		for (de = dnode_first_de(dnode); de < de_end; de = de_next_de(de), p++)
574			if (de->down) if (de_down_pointer(de) == dno) goto fnd;
575		hpfs_error(i->i_sb, "delete_empty_dnode: pointer to dnode %08x not found in dnode %08x", dno, up);
576		goto end;
577		fnd:
578		for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | 1, ((loff_t)up << 4) | p);
579		if (!down) {
580			de->down = 0;
581			le16_add_cpu(&de->length, -4);
582			le32_add_cpu(&dnode->first_free, -4);
583			memmove(de_next_de(de), (char *)de_next_de(de) + 4,
584				(char *)dnode + le32_to_cpu(dnode->first_free) - (char *)de_next_de(de));
585		} else {
586			struct dnode *d1;
587			struct quad_buffer_head qbh1;
588			*(dnode_secno *) ((void *) de + le16_to_cpu(de->length) - 4) = down;
589			if ((d1 = hpfs_map_dnode(i->i_sb, down, &qbh1))) {
590				d1->up = cpu_to_le32(up);
591				hpfs_mark_4buffers_dirty(&qbh1);
592				hpfs_brelse4(&qbh1);
593			}
594		}
595	} else {
596		hpfs_error(i->i_sb, "delete_empty_dnode: dnode %08x, first_free == %03x", dno, le32_to_cpu(dnode->first_free));
597		goto end;
598	}
599
600	if (!de->last) {
601		struct hpfs_dirent *de_next = de_next_de(de);
602		struct hpfs_dirent *de_cp;
603		struct dnode *d1;
604		struct quad_buffer_head qbh1;
605		if (!de_next->down) goto endm;
606		ndown = de_down_pointer(de_next);
607		if (!(de_cp = kmalloc(le16_to_cpu(de->length), GFP_NOFS))) {
608			pr_err("out of memory for dtree balancing\n");
609			goto endm;
610		}
611		memcpy(de_cp, de, le16_to_cpu(de->length));
612		hpfs_delete_de(i->i_sb, dnode, de);
613		hpfs_mark_4buffers_dirty(&qbh);
614		hpfs_brelse4(&qbh);
615		for_all_poss(i, hpfs_pos_subst, ((loff_t)up << 4) | p, 4);
616		for_all_poss(i, hpfs_pos_del, ((loff_t)up << 4) | p, 1);
617		if (de_cp->down) if ((d1 = hpfs_map_dnode(i->i_sb, de_down_pointer(de_cp), &qbh1))) {
618			d1->up = cpu_to_le32(ndown);
619			hpfs_mark_4buffers_dirty(&qbh1);
620			hpfs_brelse4(&qbh1);
621		}
622		hpfs_add_to_dnode(i, ndown, de_cp->name, de_cp->namelen, de_cp, de_cp->down ? de_down_pointer(de_cp) : 0);
623		/*pr_info("UP-TO-DNODE: %08x (ndown = %08x, down = %08x, dno = %08x)\n",
624		  up, ndown, down, dno);*/
625		dno = up;
626		kfree(de_cp);
627		goto try_it_again;
628	} else {
629		struct hpfs_dirent *de_prev = dnode_pre_last_de(dnode);
630		struct hpfs_dirent *de_cp;
631		struct dnode *d1;
632		struct quad_buffer_head qbh1;
633		dnode_secno dlp;
634		if (!de_prev) {
635			hpfs_error(i->i_sb, "delete_empty_dnode: empty dnode %08x", up);
636			hpfs_mark_4buffers_dirty(&qbh);
637			hpfs_brelse4(&qbh);
638			dno = up;
639			goto try_it_again;
640		}
641		if (!de_prev->down) goto endm;
642		ndown = de_down_pointer(de_prev);
643		if ((d1 = hpfs_map_dnode(i->i_sb, ndown, &qbh1))) {
644			struct hpfs_dirent *del = dnode_last_de(d1);
645			dlp = del->down ? de_down_pointer(del) : 0;
646			if (!dlp && down) {
647				if (le32_to_cpu(d1->first_free) > 2044) {
648					if (hpfs_sb(i->i_sb)->sb_chk >= 2) {
649						pr_err("unbalanced dnode tree, see hpfs.txt 4 more info\n");
650						pr_err("terminating balancing operation\n");
651					}
652					hpfs_brelse4(&qbh1);
653					goto endm;
654				}
655				if (hpfs_sb(i->i_sb)->sb_chk >= 2) {
656					pr_err("unbalanced dnode tree, see hpfs.txt 4 more info\n");
657					pr_err("goin'on\n");
658				}
659				le16_add_cpu(&del->length, 4);
660				del->down = 1;
661				le32_add_cpu(&d1->first_free, 4);
662			}
663			if (dlp && !down) {
664				le16_add_cpu(&del->length, -4);
665				del->down = 0;
666				le32_add_cpu(&d1->first_free, -4);
667			} else if (down)
668				*(__le32 *) ((void *) del + le16_to_cpu(del->length) - 4) = cpu_to_le32(down);
669		} else goto endm;
670		if (!(de_cp = kmalloc(le16_to_cpu(de_prev->length), GFP_NOFS))) {
671			pr_err("out of memory for dtree balancing\n");
672			hpfs_brelse4(&qbh1);
673			goto endm;
674		}
675		hpfs_mark_4buffers_dirty(&qbh1);
676		hpfs_brelse4(&qbh1);
677		memcpy(de_cp, de_prev, le16_to_cpu(de_prev->length));
678		hpfs_delete_de(i->i_sb, dnode, de_prev);
679		if (!de_prev->down) {
680			le16_add_cpu(&de_prev->length, 4);
681			de_prev->down = 1;
682			le32_add_cpu(&dnode->first_free, 4);
683		}
684		*(__le32 *) ((void *) de_prev + le16_to_cpu(de_prev->length) - 4) = cpu_to_le32(ndown);
685		hpfs_mark_4buffers_dirty(&qbh);
686		hpfs_brelse4(&qbh);
687		for_all_poss(i, hpfs_pos_subst, ((loff_t)up << 4) | (p - 1), 4);
688		for_all_poss(i, hpfs_pos_subst, ((loff_t)up << 4) | p, ((loff_t)up << 4) | (p - 1));
689		if (down) if ((d1 = hpfs_map_dnode(i->i_sb, de_down_pointer(de), &qbh1))) {
690			d1->up = cpu_to_le32(ndown);
691			hpfs_mark_4buffers_dirty(&qbh1);
692			hpfs_brelse4(&qbh1);
693		}
694		hpfs_add_to_dnode(i, ndown, de_cp->name, de_cp->namelen, de_cp, dlp);
695		dno = up;
696		kfree(de_cp);
697		goto try_it_again;
698	}
699	endm:
700	hpfs_mark_4buffers_dirty(&qbh);
701	end:
702	hpfs_brelse4(&qbh);
703}
704
705
706/* Delete dirent from directory */
707
708int hpfs_remove_dirent(struct inode *i, dnode_secno dno, struct hpfs_dirent *de,
709		       struct quad_buffer_head *qbh, int depth)
710{
711	struct dnode *dnode = qbh->data;
712	dnode_secno down = 0;
713	loff_t t;
714	if (de->first || de->last) {
715		hpfs_error(i->i_sb, "hpfs_remove_dirent: attempt to delete first or last dirent in dnode %08x", dno);
716		hpfs_brelse4(qbh);
717		return 1;
718	}
719	if (de->down) down = de_down_pointer(de);
720	if (depth && (de->down || (de == dnode_first_de(dnode) && de_next_de(de)->last))) {
721		if (hpfs_check_free_dnodes(i->i_sb, FREE_DNODES_DEL)) {
722			hpfs_brelse4(qbh);
723			return 2;
724		}
725	}
726	i->i_version++;
727	for_all_poss(i, hpfs_pos_del, (t = get_pos(dnode, de)) + 1, 1);
728	hpfs_delete_de(i->i_sb, dnode, de);
729	hpfs_mark_4buffers_dirty(qbh);
730	hpfs_brelse4(qbh);
731	if (down) {
732		dnode_secno a = move_to_top(i, down, dno);
733		for_all_poss(i, hpfs_pos_subst, 5, t);
734		if (a) delete_empty_dnode(i, a);
735		return !a;
736	}
737	delete_empty_dnode(i, dno);
738	return 0;
739}
740
741void hpfs_count_dnodes(struct super_block *s, dnode_secno dno, int *n_dnodes,
742		       int *n_subdirs, int *n_items)
743{
744	struct dnode *dnode;
745	struct quad_buffer_head qbh;
746	struct hpfs_dirent *de;
747	dnode_secno ptr, odno = 0;
748	int c1, c2 = 0;
749	int d1, d2 = 0;
750	go_down:
751	if (n_dnodes) (*n_dnodes)++;
752	if (hpfs_sb(s)->sb_chk)
753		if (hpfs_stop_cycles(s, dno, &c1, &c2, "hpfs_count_dnodes #1")) return;
754	ptr = 0;
755	go_up:
756	if (!(dnode = hpfs_map_dnode(s, dno, &qbh))) return;
757	if (hpfs_sb(s)->sb_chk) if (odno && odno != -1 && le32_to_cpu(dnode->up) != odno)
758		hpfs_error(s, "hpfs_count_dnodes: bad up pointer; dnode %08x, down %08x points to %08x", odno, dno, le32_to_cpu(dnode->up));
759	de = dnode_first_de(dnode);
760	if (ptr) while(1) {
761		if (de->down) if (de_down_pointer(de) == ptr) goto process_de;
762		if (de->last) {
763			hpfs_brelse4(&qbh);
764			hpfs_error(s, "hpfs_count_dnodes: pointer to dnode %08x not found in dnode %08x, got here from %08x",
765				ptr, dno, odno);
766			return;
767		}
768		de = de_next_de(de);
769	}
770	next_de:
771	if (de->down) {
772		odno = dno;
773		dno = de_down_pointer(de);
774		hpfs_brelse4(&qbh);
775		goto go_down;
776	}
777	process_de:
778	if (!de->first && !de->last && de->directory && n_subdirs) (*n_subdirs)++;
779	if (!de->first && !de->last && n_items) (*n_items)++;
780	if ((de = de_next_de(de)) < dnode_end_de(dnode)) goto next_de;
781	ptr = dno;
782	dno = le32_to_cpu(dnode->up);
783	if (dnode->root_dnode) {
784		hpfs_brelse4(&qbh);
785		return;
786	}
787	hpfs_brelse4(&qbh);
788	if (hpfs_sb(s)->sb_chk)
789		if (hpfs_stop_cycles(s, ptr, &d1, &d2, "hpfs_count_dnodes #2")) return;
790	odno = -1;
791	goto go_up;
792}
793
794static struct hpfs_dirent *map_nth_dirent(struct super_block *s, dnode_secno dno, int n,
795					  struct quad_buffer_head *qbh, struct dnode **dn)
796{
797	int i;
798	struct hpfs_dirent *de, *de_end;
799	struct dnode *dnode;
800	dnode = hpfs_map_dnode(s, dno, qbh);
801	if (!dnode) return NULL;
802	if (dn) *dn=dnode;
803	de = dnode_first_de(dnode);
804	de_end = dnode_end_de(dnode);
805	for (i = 1; de < de_end; i++, de = de_next_de(de)) {
806		if (i == n) {
807			return de;
808		}
809		if (de->last) break;
810	}
811	hpfs_brelse4(qbh);
812	hpfs_error(s, "map_nth_dirent: n too high; dnode = %08x, requested %08x", dno, n);
813	return NULL;
814}
815
816dnode_secno hpfs_de_as_down_as_possible(struct super_block *s, dnode_secno dno)
817{
818	struct quad_buffer_head qbh;
819	dnode_secno d = dno;
820	dnode_secno up = 0;
821	struct hpfs_dirent *de;
822	int c1, c2 = 0;
823
824	again:
825	if (hpfs_sb(s)->sb_chk)
826		if (hpfs_stop_cycles(s, d, &c1, &c2, "hpfs_de_as_down_as_possible"))
827			return d;
828	if (!(de = map_nth_dirent(s, d, 1, &qbh, NULL))) return dno;
829	if (hpfs_sb(s)->sb_chk)
830		if (up && le32_to_cpu(((struct dnode *)qbh.data)->up) != up)
831			hpfs_error(s, "hpfs_de_as_down_as_possible: bad up pointer; dnode %08x, down %08x points to %08x", up, d, le32_to_cpu(((struct dnode *)qbh.data)->up));
832	if (!de->down) {
833		hpfs_brelse4(&qbh);
834		return d;
835	}
836	up = d;
837	d = de_down_pointer(de);
838	hpfs_brelse4(&qbh);
839	goto again;
840}
841
842struct hpfs_dirent *map_pos_dirent(struct inode *inode, loff_t *posp,
843				   struct quad_buffer_head *qbh)
844{
845	loff_t pos;
846	unsigned c;
847	dnode_secno dno;
848	struct hpfs_dirent *de, *d;
849	struct hpfs_dirent *up_de;
850	struct hpfs_dirent *end_up_de;
851	struct dnode *dnode;
852	struct dnode *up_dnode;
853	struct quad_buffer_head qbh0;
854
855	pos = *posp;
856	dno = pos >> 6 << 2;
857	pos &= 077;
858	if (!(de = map_nth_dirent(inode->i_sb, dno, pos, qbh, &dnode)))
859		goto bail;
860
861	/* Going to the next dirent */
862	if ((d = de_next_de(de)) < dnode_end_de(dnode)) {
863		if (!(++*posp & 077)) {
864			hpfs_error(inode->i_sb,
865				"map_pos_dirent: pos crossed dnode boundary; pos = %08llx",
866				(unsigned long long)*posp);
867			goto bail;
868		}
869		/* We're going down the tree */
870		if (d->down) {
871			*posp = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, de_down_pointer(d)) << 4) + 1;
872		}
873
874		return de;
875	}
876
877	/* Going up */
878	if (dnode->root_dnode) goto bail;
879
880	if (!(up_dnode = hpfs_map_dnode(inode->i_sb, le32_to_cpu(dnode->up), &qbh0)))
881		goto bail;
882
883	end_up_de = dnode_end_de(up_dnode);
884	c = 0;
885	for (up_de = dnode_first_de(up_dnode); up_de < end_up_de;
886	     up_de = de_next_de(up_de)) {
887		if (!(++c & 077)) hpfs_error(inode->i_sb,
888			"map_pos_dirent: pos crossed dnode boundary; dnode = %08x", le32_to_cpu(dnode->up));
889		if (up_de->down && de_down_pointer(up_de) == dno) {
890			*posp = ((loff_t) le32_to_cpu(dnode->up) << 4) + c;
891			hpfs_brelse4(&qbh0);
892			return de;
893		}
894	}
895
896	hpfs_error(inode->i_sb, "map_pos_dirent: pointer to dnode %08x not found in parent dnode %08x",
897		dno, le32_to_cpu(dnode->up));
898	hpfs_brelse4(&qbh0);
899
900	bail:
901	*posp = 12;
902	return de;
903}
904
905/* Find a dirent in tree */
906
907struct hpfs_dirent *map_dirent(struct inode *inode, dnode_secno dno,
908			       const unsigned char *name, unsigned len,
909			       dnode_secno *dd, struct quad_buffer_head *qbh)
910{
911	struct dnode *dnode;
912	struct hpfs_dirent *de;
913	struct hpfs_dirent *de_end;
914	int c1, c2 = 0;
915
916	if (!S_ISDIR(inode->i_mode)) hpfs_error(inode->i_sb, "map_dirent: not a directory\n");
917	again:
918	if (hpfs_sb(inode->i_sb)->sb_chk)
919		if (hpfs_stop_cycles(inode->i_sb, dno, &c1, &c2, "map_dirent")) return NULL;
920	if (!(dnode = hpfs_map_dnode(inode->i_sb, dno, qbh))) return NULL;
921
922	de_end = dnode_end_de(dnode);
923	for (de = dnode_first_de(dnode); de < de_end; de = de_next_de(de)) {
924		int t = hpfs_compare_names(inode->i_sb, name, len, de->name, de->namelen, de->last);
925		if (!t) {
926			if (dd) *dd = dno;
927			return de;
928		}
929		if (t < 0) {
930			if (de->down) {
931				dno = de_down_pointer(de);
932				hpfs_brelse4(qbh);
933				goto again;
934			}
935		break;
936		}
937	}
938	hpfs_brelse4(qbh);
939	return NULL;
940}
941
942/*
943 * Remove empty directory. In normal cases it is only one dnode with two
944 * entries, but we must handle also such obscure cases when it's a tree
945 * of empty dnodes.
946 */
947
948void hpfs_remove_dtree(struct super_block *s, dnode_secno dno)
949{
950	struct quad_buffer_head qbh;
951	struct dnode *dnode;
952	struct hpfs_dirent *de;
953	dnode_secno d1, d2, rdno = dno;
954	while (1) {
955		if (!(dnode = hpfs_map_dnode(s, dno, &qbh))) return;
956		de = dnode_first_de(dnode);
957		if (de->last) {
958			if (de->down) d1 = de_down_pointer(de);
959			else goto error;
960			hpfs_brelse4(&qbh);
961			hpfs_free_dnode(s, dno);
962			dno = d1;
963		} else break;
964	}
965	if (!de->first) goto error;
966	d1 = de->down ? de_down_pointer(de) : 0;
967	de = de_next_de(de);
968	if (!de->last) goto error;
969	d2 = de->down ? de_down_pointer(de) : 0;
970	hpfs_brelse4(&qbh);
971	hpfs_free_dnode(s, dno);
972	do {
973		while (d1) {
974			if (!(dnode = hpfs_map_dnode(s, dno = d1, &qbh))) return;
975			de = dnode_first_de(dnode);
976			if (!de->last) goto error;
977			d1 = de->down ? de_down_pointer(de) : 0;
978			hpfs_brelse4(&qbh);
979			hpfs_free_dnode(s, dno);
980		}
981		d1 = d2;
982		d2 = 0;
983	} while (d1);
984	return;
985	error:
986	hpfs_brelse4(&qbh);
987	hpfs_free_dnode(s, dno);
988	hpfs_error(s, "directory %08x is corrupted or not empty", rdno);
989}
990
991/*
992 * Find dirent for specified fnode. Use truncated 15-char name in fnode as
993 * a help for searching.
994 */
995
996struct hpfs_dirent *map_fnode_dirent(struct super_block *s, fnode_secno fno,
997				     struct fnode *f, struct quad_buffer_head *qbh)
998{
999	unsigned char *name1;
1000	unsigned char *name2;
1001	int name1len, name2len;
1002	struct dnode *d;
1003	dnode_secno dno, downd;
1004	struct fnode *upf;
1005	struct buffer_head *bh;
1006	struct hpfs_dirent *de, *de_end;
1007	int c;
1008	int c1, c2 = 0;
1009	int d1, d2 = 0;
1010	name1 = f->name;
1011	if (!(name2 = kmalloc(256, GFP_NOFS))) {
1012		pr_err("out of memory, can't map dirent\n");
1013		return NULL;
1014	}
1015	if (f->len <= 15)
1016		memcpy(name2, name1, name1len = name2len = f->len);
1017	else {
1018		memcpy(name2, name1, 15);
1019		memset(name2 + 15, 0xff, 256 - 15);
1020		/*name2[15] = 0xff;*/
1021		name1len = 15; name2len = 256;
1022	}
1023	if (!(upf = hpfs_map_fnode(s, le32_to_cpu(f->up), &bh))) {
1024		kfree(name2);
1025		return NULL;
1026	}
1027	if (!fnode_is_dir(upf)) {
1028		brelse(bh);
1029		hpfs_error(s, "fnode %08x has non-directory parent %08x", fno, le32_to_cpu(f->up));
1030		kfree(name2);
1031		return NULL;
1032	}
1033	dno = le32_to_cpu(upf->u.external[0].disk_secno);
1034	brelse(bh);
1035	go_down:
1036	downd = 0;
1037	go_up:
1038	if (!(d = hpfs_map_dnode(s, dno, qbh))) {
1039		kfree(name2);
1040		return NULL;
1041	}
1042	de_end = dnode_end_de(d);
1043	de = dnode_first_de(d);
1044	if (downd) {
1045		while (de < de_end) {
1046			if (de->down) if (de_down_pointer(de) == downd) goto f;
1047			de = de_next_de(de);
1048		}
1049		hpfs_error(s, "pointer to dnode %08x not found in dnode %08x", downd, dno);
1050		hpfs_brelse4(qbh);
1051		kfree(name2);
1052		return NULL;
1053	}
1054	next_de:
1055	if (le32_to_cpu(de->fnode) == fno) {
1056		kfree(name2);
1057		return de;
1058	}
1059	c = hpfs_compare_names(s, name1, name1len, de->name, de->namelen, de->last);
1060	if (c < 0 && de->down) {
1061		dno = de_down_pointer(de);
1062		hpfs_brelse4(qbh);
1063		if (hpfs_sb(s)->sb_chk)
1064			if (hpfs_stop_cycles(s, dno, &c1, &c2, "map_fnode_dirent #1")) {
1065				kfree(name2);
1066				return NULL;
1067		}
1068		goto go_down;
1069	}
1070	f:
1071	if (le32_to_cpu(de->fnode) == fno) {
1072		kfree(name2);
1073		return de;
1074	}
1075	c = hpfs_compare_names(s, name2, name2len, de->name, de->namelen, de->last);
1076	if (c < 0 && !de->last) goto not_found;
1077	if ((de = de_next_de(de)) < de_end) goto next_de;
1078	if (d->root_dnode) goto not_found;
1079	downd = dno;
1080	dno = le32_to_cpu(d->up);
1081	hpfs_brelse4(qbh);
1082	if (hpfs_sb(s)->sb_chk)
1083		if (hpfs_stop_cycles(s, downd, &d1, &d2, "map_fnode_dirent #2")) {
1084			kfree(name2);
1085			return NULL;
1086		}
1087	goto go_up;
1088	not_found:
1089	hpfs_brelse4(qbh);
1090	hpfs_error(s, "dirent for fnode %08x not found", fno);
1091	kfree(name2);
1092	return NULL;
1093}
1094