xref: /netbsd-src/sys/fs/udf/udf_allocation.c (revision 313c6c94c424eed90c7b7e494aa83308a0a5d0ce)
1 /* $NetBSD: udf_allocation.c,v 1.23 2009/05/19 16:24:05 reinoud Exp $ */
2 
3 /*
4  * Copyright (c) 2006, 2008 Reinoud Zandijk
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  */
28 
29 #include <sys/cdefs.h>
30 #ifndef lint
31 __KERNEL_RCSID(0, "$NetBSD: udf_allocation.c,v 1.23 2009/05/19 16:24:05 reinoud Exp $");
32 #endif /* not lint */
33 
34 
35 #if defined(_KERNEL_OPT)
36 #include "opt_quota.h"
37 #include "opt_compat_netbsd.h"
38 #endif
39 
40 /* TODO strip */
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/sysctl.h>
44 #include <sys/namei.h>
45 #include <sys/proc.h>
46 #include <sys/kernel.h>
47 #include <sys/vnode.h>
48 #include <miscfs/genfs/genfs_node.h>
49 #include <sys/mount.h>
50 #include <sys/buf.h>
51 #include <sys/file.h>
52 #include <sys/device.h>
53 #include <sys/disklabel.h>
54 #include <sys/ioctl.h>
55 #include <sys/malloc.h>
56 #include <sys/dirent.h>
57 #include <sys/stat.h>
58 #include <sys/conf.h>
59 #include <sys/kauth.h>
60 #include <sys/kthread.h>
61 #include <dev/clock_subr.h>
62 
63 #include <fs/udf/ecma167-udf.h>
64 #include <fs/udf/udf_mount.h>
65 
66 #include "udf.h"
67 #include "udf_subr.h"
68 #include "udf_bswap.h"
69 
70 
71 #define VTOI(vnode) ((struct udf_node *) vnode->v_data)
72 
73 static void udf_record_allocation_in_node(struct udf_mount *ump,
74 	struct buf *buf, uint16_t vpart_num, uint64_t *mapping,
75 	struct long_ad *node_ad_cpy);
76 
77 /*
78  * IDEA/BUSY: Each udf_node gets its own extentwalker state for all operations;
79  * this will hopefully/likely reduce O(nlog(n)) to O(1) for most functionality
80  * since actions are most likely sequencial and thus seeking doesn't need
81  * searching for the same or adjacent position again.
82  */
83 
84 /* --------------------------------------------------------------------- */
85 
86 #if 0
87 #if 1
88 static void
89 udf_node_dump(struct udf_node *udf_node) {
90 	struct file_entry    *fe;
91 	struct extfile_entry *efe;
92 	struct icb_tag *icbtag;
93 	struct long_ad s_ad;
94 	uint64_t inflen;
95 	uint32_t icbflags, addr_type;
96 	uint32_t len, lb_num;
97 	uint32_t flags;
98 	int part_num;
99 	int lb_size, eof, slot;
100 
101 	if ((udf_verbose & UDF_DEBUG_NODEDUMP) == 0)
102 		return;
103 
104 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
105 
106 	fe  = udf_node->fe;
107 	efe = udf_node->efe;
108 	if (fe) {
109 		icbtag = &fe->icbtag;
110 		inflen = udf_rw64(fe->inf_len);
111 	} else {
112 		icbtag = &efe->icbtag;
113 		inflen = udf_rw64(efe->inf_len);
114 	}
115 
116 	icbflags   = udf_rw16(icbtag->flags);
117 	addr_type  = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
118 
119 	printf("udf_node_dump %p :\n", udf_node);
120 
121 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
122 		printf("\tIntern alloc, len = %"PRIu64"\n", inflen);
123 		return;
124 	}
125 
126 	printf("\tInflen  = %"PRIu64"\n", inflen);
127 	printf("\t\t");
128 
129 	slot = 0;
130 	for (;;) {
131 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
132 		if (eof)
133 			break;
134 		part_num = udf_rw16(s_ad.loc.part_num);
135 		lb_num = udf_rw32(s_ad.loc.lb_num);
136 		len   = udf_rw32(s_ad.len);
137 		flags = UDF_EXT_FLAGS(len);
138 		len   = UDF_EXT_LEN(len);
139 
140 		printf("[");
141 		if (part_num >= 0)
142 			printf("part %d, ", part_num);
143 		printf("lb_num %d, len %d", lb_num, len);
144 		if (flags)
145 			printf(", flags %d", flags>>30);
146 		printf("] ");
147 
148 		if (flags == UDF_EXT_REDIRECT) {
149 			printf("\n\textent END\n\tallocation extent\n\t\t");
150 		}
151 
152 		slot++;
153 	}
154 	printf("\n\tl_ad END\n\n");
155 }
156 #else
157 #define udf_node_dump(a)
158 #endif
159 
160 
161 static void
162 udf_assert_allocated(struct udf_mount *ump, uint16_t vpart_num,
163 	uint32_t lb_num, uint32_t num_lb)
164 {
165 	struct udf_bitmap *bitmap;
166 	struct part_desc *pdesc;
167 	uint32_t ptov;
168 	uint32_t bitval;
169 	uint8_t *bpos;
170 	int bit;
171 	int phys_part;
172 	int ok;
173 
174 	DPRINTF(PARANOIA, ("udf_assert_allocated: check virt lbnum %d "
175 			  "part %d + %d sect\n", lb_num, vpart_num, num_lb));
176 
177 	/* get partition backing up this vpart_num */
178 	pdesc = ump->partitions[ump->vtop[vpart_num]];
179 
180 	switch (ump->vtop_tp[vpart_num]) {
181 	case UDF_VTOP_TYPE_PHYS :
182 	case UDF_VTOP_TYPE_SPARABLE :
183 		/* free space to freed or unallocated space bitmap */
184 		ptov      = udf_rw32(pdesc->start_loc);
185 		phys_part = ump->vtop[vpart_num];
186 
187 		/* use unallocated bitmap */
188 		bitmap = &ump->part_unalloc_bits[phys_part];
189 
190 		/* if no bitmaps are defined, bail out */
191 		if (bitmap->bits == NULL)
192 			break;
193 
194 		/* check bits */
195 		KASSERT(bitmap->bits);
196 		ok = 1;
197 		bpos = bitmap->bits + lb_num/8;
198 		bit  = lb_num % 8;
199 		while (num_lb > 0) {
200 			bitval = (1 << bit);
201 			DPRINTF(PARANOIA, ("XXX : check %d, %p, bit %d\n",
202 				lb_num, bpos, bit));
203 			KASSERT(bitmap->bits + lb_num/8 == bpos);
204 			if (*bpos & bitval) {
205 				printf("\tlb_num %d is NOT marked busy\n",
206 					lb_num);
207 				ok = 0;
208 			}
209 			lb_num++; num_lb--;
210 			bit = (bit + 1) % 8;
211 			if (bit == 0)
212 				bpos++;
213 		}
214 		if (!ok) {
215 			/* KASSERT(0); */
216 		}
217 
218 		break;
219 	case UDF_VTOP_TYPE_VIRT :
220 		/* TODO check space */
221 		KASSERT(num_lb == 1);
222 		break;
223 	case UDF_VTOP_TYPE_META :
224 		/* TODO check space in the metadata bitmap */
225 	default:
226 		/* not implemented */
227 		break;
228 	}
229 }
230 
231 
232 static void
233 udf_node_sanity_check(struct udf_node *udf_node,
234 		uint64_t *cnt_inflen, uint64_t *cnt_logblksrec)
235 {
236 	union dscrptr *dscr;
237 	struct file_entry    *fe;
238 	struct extfile_entry *efe;
239 	struct icb_tag *icbtag;
240 	struct long_ad  s_ad;
241 	uint64_t inflen, logblksrec;
242 	uint32_t icbflags, addr_type;
243 	uint32_t len, lb_num, l_ea, l_ad, max_l_ad;
244 	uint16_t part_num;
245 	uint8_t *data_pos;
246 	int dscr_size, lb_size, flags, whole_lb;
247 	int i, slot, eof;
248 
249 //	KASSERT(mutex_owned(&udf_node->ump->allocate_mutex));
250 
251 	if (1)
252 		udf_node_dump(udf_node);
253 
254 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
255 
256 	fe  = udf_node->fe;
257 	efe = udf_node->efe;
258 	if (fe) {
259 		dscr       = (union dscrptr *) fe;
260 		icbtag     = &fe->icbtag;
261 		inflen     = udf_rw64(fe->inf_len);
262 		dscr_size  = sizeof(struct file_entry) -1;
263 		logblksrec = udf_rw64(fe->logblks_rec);
264 		l_ad       = udf_rw32(fe->l_ad);
265 		l_ea       = udf_rw32(fe->l_ea);
266 	} else {
267 		dscr       = (union dscrptr *) efe;
268 		icbtag     = &efe->icbtag;
269 		inflen     = udf_rw64(efe->inf_len);
270 		dscr_size  = sizeof(struct extfile_entry) -1;
271 		logblksrec = udf_rw64(efe->logblks_rec);
272 		l_ad       = udf_rw32(efe->l_ad);
273 		l_ea       = udf_rw32(efe->l_ea);
274 	}
275 	data_pos  = (uint8_t *) dscr + dscr_size + l_ea;
276 	max_l_ad   = lb_size - dscr_size - l_ea;
277 	icbflags   = udf_rw16(icbtag->flags);
278 	addr_type  = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
279 
280 	/* check if tail is zero */
281 	DPRINTF(PARANOIA, ("Sanity check blank tail\n"));
282 	for (i = l_ad; i < max_l_ad; i++) {
283 		if (data_pos[i] != 0)
284 			printf( "sanity_check: violation: node byte %d "
285 				"has value %d\n", i, data_pos[i]);
286 	}
287 
288 	/* reset counters */
289 	*cnt_inflen     = 0;
290 	*cnt_logblksrec = 0;
291 
292 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
293 		KASSERT(l_ad <= max_l_ad);
294 		KASSERT(l_ad == inflen);
295 		*cnt_inflen = inflen;
296 		return;
297 	}
298 
299 	/* start counting */
300 	whole_lb = 1;
301 	slot = 0;
302 	for (;;) {
303 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
304 		if (eof)
305 			break;
306 		KASSERT(whole_lb == 1);
307 
308 		part_num = udf_rw16(s_ad.loc.part_num);
309 		lb_num = udf_rw32(s_ad.loc.lb_num);
310 		len   = udf_rw32(s_ad.len);
311 		flags = UDF_EXT_FLAGS(len);
312 		len   = UDF_EXT_LEN(len);
313 
314 		if (flags != UDF_EXT_REDIRECT) {
315 			*cnt_inflen += len;
316 			if (flags == UDF_EXT_ALLOCATED) {
317 				*cnt_logblksrec += (len + lb_size -1) / lb_size;
318 			}
319 		} else {
320 			KASSERT(len == lb_size);
321 		}
322 		/* check allocation */
323 		if (flags == UDF_EXT_ALLOCATED)
324 			udf_assert_allocated(udf_node->ump, part_num, lb_num,
325 				(len + lb_size - 1) / lb_size);
326 
327 		/* check whole lb */
328 		whole_lb = ((len % lb_size) == 0);
329 
330 		slot++;
331 	}
332 	/* rest should be zero (ad_off > l_ad < max_l_ad - adlen) */
333 
334 	KASSERT(*cnt_inflen == inflen);
335 	KASSERT(*cnt_logblksrec == logblksrec);
336 
337 //	KASSERT(mutex_owned(&udf_node->ump->allocate_mutex));
338 }
339 #else
340 static void
341 udf_node_sanity_check(struct udf_node *udf_node,
342 		uint64_t *cnt_inflen, uint64_t *cnt_logblksrec) {
343 	struct file_entry    *fe;
344 	struct extfile_entry *efe;
345 	struct icb_tag *icbtag;
346 	uint64_t inflen, logblksrec;
347 	int dscr_size, lb_size;
348 
349 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
350 
351 	fe  = udf_node->fe;
352 	efe = udf_node->efe;
353 	if (fe) {
354 		icbtag = &fe->icbtag;
355 		inflen = udf_rw64(fe->inf_len);
356 		dscr_size  = sizeof(struct file_entry) -1;
357 		logblksrec = udf_rw64(fe->logblks_rec);
358 	} else {
359 		icbtag = &efe->icbtag;
360 		inflen = udf_rw64(efe->inf_len);
361 		dscr_size  = sizeof(struct extfile_entry) -1;
362 		logblksrec = udf_rw64(efe->logblks_rec);
363 	}
364 	*cnt_logblksrec = logblksrec;
365 	*cnt_inflen     = inflen;
366 }
367 #endif
368 
369 /* --------------------------------------------------------------------- */
370 
371 int
372 udf_translate_vtop(struct udf_mount *ump, struct long_ad *icb_loc,
373 		   uint32_t *lb_numres, uint32_t *extres)
374 {
375 	struct part_desc       *pdesc;
376 	struct spare_map_entry *sme;
377 	struct long_ad s_icb_loc;
378 	uint64_t foffset, end_foffset;
379 	uint32_t lb_size, len;
380 	uint32_t lb_num, lb_rel, lb_packet;
381 	uint32_t udf_rw32_lbmap, ext_offset;
382 	uint16_t vpart;
383 	int rel, part, error, eof, slot, flags;
384 
385 	assert(ump && icb_loc && lb_numres);
386 
387 	vpart  = udf_rw16(icb_loc->loc.part_num);
388 	lb_num = udf_rw32(icb_loc->loc.lb_num);
389 	if (vpart > UDF_VTOP_RAWPART)
390 		return EINVAL;
391 
392 translate_again:
393 	part = ump->vtop[vpart];
394 	pdesc = ump->partitions[part];
395 
396 	switch (ump->vtop_tp[vpart]) {
397 	case UDF_VTOP_TYPE_RAW :
398 		/* 1:1 to the end of the device */
399 		*lb_numres = lb_num;
400 		*extres = INT_MAX;
401 		return 0;
402 	case UDF_VTOP_TYPE_PHYS :
403 		/* transform into its disc logical block */
404 		if (lb_num > udf_rw32(pdesc->part_len))
405 			return EINVAL;
406 		*lb_numres = lb_num + udf_rw32(pdesc->start_loc);
407 
408 		/* extent from here to the end of the partition */
409 		*extres = udf_rw32(pdesc->part_len) - lb_num;
410 		return 0;
411 	case UDF_VTOP_TYPE_VIRT :
412 		/* only maps one logical block, lookup in VAT */
413 		if (lb_num >= ump->vat_entries)		/* XXX > or >= ? */
414 			return EINVAL;
415 
416 		/* lookup in virtual allocation table file */
417 		mutex_enter(&ump->allocate_mutex);
418 		error = udf_vat_read(ump->vat_node,
419 				(uint8_t *) &udf_rw32_lbmap, 4,
420 				ump->vat_offset + lb_num * 4);
421 		mutex_exit(&ump->allocate_mutex);
422 
423 		if (error)
424 			return error;
425 
426 		lb_num = udf_rw32(udf_rw32_lbmap);
427 
428 		/* transform into its disc logical block */
429 		if (lb_num > udf_rw32(pdesc->part_len))
430 			return EINVAL;
431 		*lb_numres = lb_num + udf_rw32(pdesc->start_loc);
432 
433 		/* just one logical block */
434 		*extres = 1;
435 		return 0;
436 	case UDF_VTOP_TYPE_SPARABLE :
437 		/* check if the packet containing the lb_num is remapped */
438 		lb_packet = lb_num / ump->sparable_packet_size;
439 		lb_rel    = lb_num % ump->sparable_packet_size;
440 
441 		for (rel = 0; rel < udf_rw16(ump->sparing_table->rt_l); rel++) {
442 			sme = &ump->sparing_table->entries[rel];
443 			if (lb_packet == udf_rw32(sme->org)) {
444 				/* NOTE maps to absolute disc logical block! */
445 				*lb_numres = udf_rw32(sme->map) + lb_rel;
446 				*extres    = ump->sparable_packet_size - lb_rel;
447 				return 0;
448 			}
449 		}
450 
451 		/* transform into its disc logical block */
452 		if (lb_num > udf_rw32(pdesc->part_len))
453 			return EINVAL;
454 		*lb_numres = lb_num + udf_rw32(pdesc->start_loc);
455 
456 		/* rest of block */
457 		*extres = ump->sparable_packet_size - lb_rel;
458 		return 0;
459 	case UDF_VTOP_TYPE_META :
460 		/* we have to look into the file's allocation descriptors */
461 
462 		/* use metadatafile allocation mutex */
463 		lb_size = udf_rw32(ump->logical_vol->lb_size);
464 
465 		UDF_LOCK_NODE(ump->metadata_node, 0);
466 
467 		/* get first overlapping extent */
468 		foffset = 0;
469 		slot    = 0;
470 		for (;;) {
471 			udf_get_adslot(ump->metadata_node,
472 				slot, &s_icb_loc, &eof);
473 			DPRINTF(ADWLK, ("slot %d, eof = %d, flags = %d, "
474 				"len = %d, lb_num = %d, part = %d\n",
475 				slot, eof,
476 				UDF_EXT_FLAGS(udf_rw32(s_icb_loc.len)),
477 				UDF_EXT_LEN(udf_rw32(s_icb_loc.len)),
478 				udf_rw32(s_icb_loc.loc.lb_num),
479 				udf_rw16(s_icb_loc.loc.part_num)));
480 			if (eof) {
481 				DPRINTF(TRANSLATE,
482 					("Meta partition translation "
483 					 "failed: can't seek location\n"));
484 				UDF_UNLOCK_NODE(ump->metadata_node, 0);
485 				return EINVAL;
486 			}
487 			len   = udf_rw32(s_icb_loc.len);
488 			flags = UDF_EXT_FLAGS(len);
489 			len   = UDF_EXT_LEN(len);
490 
491 			if (flags == UDF_EXT_REDIRECT) {
492 				slot++;
493 				continue;
494 			}
495 
496 			end_foffset = foffset + len;
497 
498 			if (end_foffset > lb_num * lb_size)
499 				break;	/* found */
500 			foffset = end_foffset;
501 			slot++;
502 		}
503 		/* found overlapping slot */
504 		ext_offset = lb_num * lb_size - foffset;
505 
506 		/* process extent offset */
507 		lb_num   = udf_rw32(s_icb_loc.loc.lb_num);
508 		vpart    = udf_rw16(s_icb_loc.loc.part_num);
509 		lb_num  += (ext_offset + lb_size -1) / lb_size;
510 		ext_offset = 0;
511 
512 		UDF_UNLOCK_NODE(ump->metadata_node, 0);
513 		if (flags != UDF_EXT_ALLOCATED) {
514 			DPRINTF(TRANSLATE, ("Metadata partition translation "
515 					    "failed: not allocated\n"));
516 			return EINVAL;
517 		}
518 
519 		/*
520 		 * vpart and lb_num are updated, translate again since we
521 		 * might be mapped on sparable media
522 		 */
523 		goto translate_again;
524 	default:
525 		printf("UDF vtop translation scheme %d unimplemented yet\n",
526 			ump->vtop_tp[vpart]);
527 	}
528 
529 	return EINVAL;
530 }
531 
532 
533 /* XXX  provisional primitive braindead version */
534 /* TODO use ext_res */
535 void
536 udf_translate_vtop_list(struct udf_mount *ump, uint32_t sectors,
537 	uint16_t vpart_num, uint64_t *lmapping, uint64_t *pmapping)
538 {
539 	struct long_ad loc;
540 	uint32_t lb_numres, ext_res;
541 	int sector;
542 
543 	for (sector = 0; sector < sectors; sector++) {
544 		memset(&loc, 0, sizeof(struct long_ad));
545 		loc.loc.part_num = udf_rw16(vpart_num);
546 		loc.loc.lb_num   = udf_rw32(*lmapping);
547 		udf_translate_vtop(ump, &loc, &lb_numres, &ext_res);
548 		*pmapping = lb_numres;
549 		lmapping++; pmapping++;
550 	}
551 }
552 
553 
554 /* --------------------------------------------------------------------- */
555 
556 /*
557  * Translate an extent (in logical_blocks) into logical block numbers; used
558  * for read and write operations. DOESNT't check extents.
559  */
560 
561 int
562 udf_translate_file_extent(struct udf_node *udf_node,
563 		          uint32_t from, uint32_t num_lb,
564 			  uint64_t *map)
565 {
566 	struct udf_mount *ump;
567 	struct icb_tag *icbtag;
568 	struct long_ad t_ad, s_ad;
569 	uint64_t transsec;
570 	uint64_t foffset, end_foffset;
571 	uint32_t transsec32;
572 	uint32_t lb_size;
573 	uint32_t ext_offset;
574 	uint32_t lb_num, len;
575 	uint32_t overlap, translen;
576 	uint16_t vpart_num;
577 	int eof, error, flags;
578 	int slot, addr_type, icbflags;
579 
580 	if (!udf_node)
581 		return ENOENT;
582 
583 	KASSERT(num_lb > 0);
584 
585 	UDF_LOCK_NODE(udf_node, 0);
586 
587 	/* initialise derivative vars */
588 	ump = udf_node->ump;
589 	lb_size = udf_rw32(ump->logical_vol->lb_size);
590 
591 	if (udf_node->fe) {
592 		icbtag = &udf_node->fe->icbtag;
593 	} else {
594 		icbtag = &udf_node->efe->icbtag;
595 	}
596 	icbflags  = udf_rw16(icbtag->flags);
597 	addr_type = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
598 
599 	/* do the work */
600 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
601 		*map = UDF_TRANS_INTERN;
602 		UDF_UNLOCK_NODE(udf_node, 0);
603 		return 0;
604 	}
605 
606 	/* find first overlapping extent */
607 	foffset = 0;
608 	slot    = 0;
609 	for (;;) {
610 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
611 		DPRINTF(ADWLK, ("slot %d, eof = %d, flags = %d, len = %d, "
612 			"lb_num = %d, part = %d\n", slot, eof,
613 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)),
614 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
615 			udf_rw32(s_ad.loc.lb_num),
616 			udf_rw16(s_ad.loc.part_num)));
617 		if (eof) {
618 			DPRINTF(TRANSLATE,
619 				("Translate file extent "
620 				 "failed: can't seek location\n"));
621 			UDF_UNLOCK_NODE(udf_node, 0);
622 			return EINVAL;
623 		}
624 		len    = udf_rw32(s_ad.len);
625 		flags  = UDF_EXT_FLAGS(len);
626 		len    = UDF_EXT_LEN(len);
627 		lb_num = udf_rw32(s_ad.loc.lb_num);
628 
629 		if (flags == UDF_EXT_REDIRECT) {
630 			slot++;
631 			continue;
632 		}
633 
634 		end_foffset = foffset + len;
635 
636 		if (end_foffset > from * lb_size)
637 			break;	/* found */
638 		foffset = end_foffset;
639 		slot++;
640 	}
641 	/* found overlapping slot */
642 	ext_offset = from * lb_size - foffset;
643 
644 	for (;;) {
645 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
646 		DPRINTF(ADWLK, ("slot %d, eof = %d, flags = %d, len = %d, "
647 			"lb_num = %d, part = %d\n", slot, eof,
648 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)),
649 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
650 			udf_rw32(s_ad.loc.lb_num),
651 			udf_rw16(s_ad.loc.part_num)));
652 		if (eof) {
653 			DPRINTF(TRANSLATE,
654 				("Translate file extent "
655 				 "failed: past eof\n"));
656 			UDF_UNLOCK_NODE(udf_node, 0);
657 			return EINVAL;
658 		}
659 
660 		len    = udf_rw32(s_ad.len);
661 		flags  = UDF_EXT_FLAGS(len);
662 		len    = UDF_EXT_LEN(len);
663 
664 		lb_num    = udf_rw32(s_ad.loc.lb_num);
665 		vpart_num = udf_rw16(s_ad.loc.part_num);
666 
667 		end_foffset = foffset + len;
668 
669 		/* process extent, don't forget to advance on ext_offset! */
670 		lb_num  += (ext_offset + lb_size -1) / lb_size;
671 		overlap  = (len - ext_offset + lb_size -1) / lb_size;
672 		ext_offset = 0;
673 
674 		/*
675 		 * note that the while(){} is nessisary for the extent that
676 		 * the udf_translate_vtop() returns doens't have to span the
677 		 * whole extent.
678 		 */
679 
680 		overlap = MIN(overlap, num_lb);
681 		while (overlap && (flags != UDF_EXT_REDIRECT)) {
682 			switch (flags) {
683 			case UDF_EXT_FREE :
684 			case UDF_EXT_ALLOCATED_BUT_NOT_USED :
685 				transsec = UDF_TRANS_ZERO;
686 				translen = overlap;
687 				while (overlap && num_lb && translen) {
688 					*map++ = transsec;
689 					lb_num++;
690 					overlap--; num_lb--; translen--;
691 				}
692 				break;
693 			case UDF_EXT_ALLOCATED :
694 				t_ad.loc.lb_num   = udf_rw32(lb_num);
695 				t_ad.loc.part_num = udf_rw16(vpart_num);
696 				error = udf_translate_vtop(ump,
697 						&t_ad, &transsec32, &translen);
698 				transsec = transsec32;
699 				if (error) {
700 					UDF_UNLOCK_NODE(udf_node, 0);
701 					return error;
702 				}
703 				while (overlap && num_lb && translen) {
704 					*map++ = transsec;
705 					lb_num++; transsec++;
706 					overlap--; num_lb--; translen--;
707 				}
708 				break;
709 			default:
710 				DPRINTF(TRANSLATE,
711 					("Translate file extent "
712 					 "failed: bad flags %x\n", flags));
713 				UDF_UNLOCK_NODE(udf_node, 0);
714 				return EINVAL;
715 			}
716 		}
717 		if (num_lb == 0)
718 			break;
719 
720 		if (flags != UDF_EXT_REDIRECT)
721 			foffset = end_foffset;
722 		slot++;
723 	}
724 	UDF_UNLOCK_NODE(udf_node, 0);
725 
726 	return 0;
727 }
728 
729 /* --------------------------------------------------------------------- */
730 
731 static int
732 udf_search_free_vatloc(struct udf_mount *ump, uint32_t *lbnumres)
733 {
734 	uint32_t lb_size, lb_num, lb_map, udf_rw32_lbmap;
735 	uint8_t *blob;
736 	int entry, chunk, found, error;
737 
738 	KASSERT(ump);
739 	KASSERT(ump->logical_vol);
740 
741 	lb_size = udf_rw32(ump->logical_vol->lb_size);
742 	blob = malloc(lb_size, M_UDFTEMP, M_WAITOK);
743 
744 	/* TODO static allocation of search chunk */
745 
746 	lb_num = MIN(ump->vat_entries, ump->vat_last_free_lb);
747 	found  = 0;
748 	error  = 0;
749 	entry  = 0;
750 	do {
751 		chunk = MIN(lb_size, (ump->vat_entries - lb_num) * 4);
752 		if (chunk <= 0)
753 			break;
754 		/* load in chunk */
755 		error = udf_vat_read(ump->vat_node, blob, chunk,
756 				ump->vat_offset + lb_num * 4);
757 
758 		if (error)
759 			break;
760 
761 		/* search this chunk */
762 		for (entry=0; entry < chunk /4; entry++, lb_num++) {
763 			udf_rw32_lbmap = *((uint32_t *) (blob + entry * 4));
764 			lb_map = udf_rw32(udf_rw32_lbmap);
765 			if (lb_map == 0xffffffff) {
766 				found = 1;
767 				break;
768 			}
769 		}
770 	} while (!found);
771 	if (error) {
772 		printf("udf_search_free_vatloc: error reading in vat chunk "
773 			"(lb %d, size %d)\n", lb_num, chunk);
774 	}
775 
776 	if (!found) {
777 		/* extend VAT */
778 		DPRINTF(WRITE, ("udf_search_free_vatloc: extending\n"));
779 		lb_num = ump->vat_entries;
780 		ump->vat_entries++;
781 	}
782 
783 	/* mark entry with initialiser just in case */
784 	lb_map = udf_rw32(0xfffffffe);
785 	udf_vat_write(ump->vat_node, (uint8_t *) &lb_map, 4,
786 		ump->vat_offset + lb_num *4);
787 	ump->vat_last_free_lb = lb_num;
788 
789 	free(blob, M_UDFTEMP);
790 	*lbnumres = lb_num;
791 	return 0;
792 }
793 
794 
795 static void
796 udf_bitmap_allocate(struct udf_bitmap *bitmap, int ismetadata,
797 	uint32_t *num_lb, uint64_t *lmappos)
798 {
799 	uint32_t offset, lb_num, bit;
800 	int32_t  diff;
801 	uint8_t *bpos;
802 	int pass;
803 
804 	if (!ismetadata) {
805 		/* heuristic to keep the two pointers not too close */
806 		diff = bitmap->data_pos - bitmap->metadata_pos;
807 		if ((diff >= 0) && (diff < 1024))
808 			bitmap->data_pos = bitmap->metadata_pos + 1024;
809 	}
810 	offset = ismetadata ? bitmap->metadata_pos : bitmap->data_pos;
811 	offset &= ~7;
812 	for (pass = 0; pass < 2; pass++) {
813 		if (offset >= bitmap->max_offset)
814 			offset = 0;
815 
816 		while (offset < bitmap->max_offset) {
817 			if (*num_lb == 0)
818 				break;
819 
820 			/* use first bit not set */
821 			bpos  = bitmap->bits + offset/8;
822 			bit = ffs(*bpos);	/* returns 0 or 1..8 */
823 			if (bit == 0) {
824 				offset += 8;
825 				continue;
826 			}
827 
828 			/* check for ffs overshoot */
829 			if (offset + bit-1 >= bitmap->max_offset) {
830 				offset = bitmap->max_offset;
831 				break;
832 			}
833 
834 			DPRINTF(PARANOIA, ("XXX : allocate %d, %p, bit %d\n",
835 				offset + bit -1, bpos, bit-1));
836 			*bpos &= ~(1 << (bit-1));
837 			lb_num = offset + bit-1;
838 			*lmappos++ = lb_num;
839 			*num_lb = *num_lb - 1;
840 			// offset = (offset & ~7);
841 		}
842 	}
843 
844 	if (ismetadata) {
845 		bitmap->metadata_pos = offset;
846 	} else {
847 		bitmap->data_pos = offset;
848 	}
849 }
850 
851 
852 static void
853 udf_bitmap_free(struct udf_bitmap *bitmap, uint32_t lb_num, uint32_t num_lb)
854 {
855 	uint32_t offset;
856 	uint32_t bit, bitval;
857 	uint8_t *bpos;
858 
859 	offset = lb_num;
860 
861 	/* starter bits */
862 	bpos = bitmap->bits + offset/8;
863 	bit = offset % 8;
864 	while ((bit != 0) && (num_lb > 0)) {
865 		bitval = (1 << bit);
866 		KASSERT((*bpos & bitval) == 0);
867 		DPRINTF(PARANOIA, ("XXX : free %d, %p, %d\n",
868 			offset, bpos, bit));
869 		*bpos |= bitval;
870 		offset++; num_lb--;
871 		bit = (bit + 1) % 8;
872 	}
873 	if (num_lb == 0)
874 		return;
875 
876 	/* whole bytes */
877 	KASSERT(bit == 0);
878 	bpos = bitmap->bits + offset / 8;
879 	while (num_lb >= 8) {
880 		KASSERT((*bpos == 0));
881 		DPRINTF(PARANOIA, ("XXX : free %d + 8, %p\n", offset, bpos));
882 		*bpos = 255;
883 		offset += 8; num_lb -= 8;
884 		bpos++;
885 	}
886 
887 	/* stop bits */
888 	KASSERT(num_lb < 8);
889 	bit = 0;
890 	while (num_lb > 0) {
891 		bitval = (1 << bit);
892 		KASSERT((*bpos & bitval) == 0);
893 		DPRINTF(PARANOIA, ("XXX : free %d, %p, %d\n",
894 			offset, bpos, bit));
895 		*bpos |= bitval;
896 		offset++; num_lb--;
897 		bit = (bit + 1) % 8;
898 	}
899 }
900 
901 
902 /* allocate a contiguous sequence of sectornumbers */
903 static int
904 udf_allocate_space(struct udf_mount *ump, int udf_c_type,
905 	uint16_t vpart_num, uint32_t num_lb, uint64_t *lmapping)
906 {
907 	struct mmc_trackinfo *alloc_track, *other_track;
908 	struct udf_bitmap *bitmap;
909 	struct part_desc *pdesc;
910 	struct logvol_int_desc *lvid;
911 	uint64_t *lmappos;
912 	uint32_t ptov, lb_num, *freepos, free_lbs;
913 	int lb_size, alloc_num_lb;
914 	int alloc_type, error;
915 	int is_node;
916 
917 	DPRINTF(CALL, ("udf_allocate_space(ctype %d, vpart %d, num_lb %d\n",
918 		udf_c_type, vpart_num, num_lb));
919 	mutex_enter(&ump->allocate_mutex);
920 
921 	lb_size = udf_rw32(ump->logical_vol->lb_size);
922 	KASSERT(lb_size == ump->discinfo.sector_size);
923 
924 	/* XXX TODO check disc space */
925 
926 	alloc_type =  ump->vtop_alloc[vpart_num];
927 	is_node    = (udf_c_type == UDF_C_NODE);
928 
929 	lmappos = lmapping;
930 	error = 0;
931 	switch (alloc_type) {
932 	case UDF_ALLOC_VAT :
933 		/* search empty slot in VAT file */
934 		KASSERT(num_lb == 1);
935 		error = udf_search_free_vatloc(ump, &lb_num);
936 		if (!error)
937 			*lmappos = lb_num;
938 		break;
939 	case UDF_ALLOC_SEQUENTIAL :
940 		/* sequential allocation on recordable media */
941 		/* get partition backing up this vpart_num_num */
942 		pdesc = ump->partitions[ump->vtop[vpart_num]];
943 
944 		/* calculate offset from physical base partition */
945 		ptov  = udf_rw32(pdesc->start_loc);
946 
947 		/* get our track descriptors */
948 		if (vpart_num == ump->node_part) {
949 			alloc_track = &ump->metadata_track;
950 			other_track = &ump->data_track;
951 		} else {
952 			alloc_track = &ump->data_track;
953 			other_track = &ump->metadata_track;
954 		}
955 
956 		/* allocate */
957 		for (lb_num = 0; lb_num < num_lb; lb_num++) {
958 			*lmappos++ = alloc_track->next_writable - ptov;
959 			alloc_track->next_writable++;
960 			alloc_track->free_blocks--;
961 		}
962 
963 		/* keep other track up-to-date */
964 		if (alloc_track->tracknr == other_track->tracknr)
965 			memcpy(other_track, alloc_track,
966 				sizeof(struct mmc_trackinfo));
967 		break;
968 	case UDF_ALLOC_SPACEMAP :
969 		/* try to allocate on unallocated bits */
970 		alloc_num_lb = num_lb;
971 		bitmap = &ump->part_unalloc_bits[vpart_num];
972 		udf_bitmap_allocate(bitmap, is_node, &alloc_num_lb, lmappos);
973 		ump->lvclose |= UDF_WRITE_PART_BITMAPS;
974 
975 		/* have we allocated all? */
976 		if (alloc_num_lb) {
977 			/* TODO convert freed to unalloc and try again */
978 			/* free allocated piece for now */
979 			lmappos = lmapping;
980 			for (lb_num=0; lb_num < num_lb-alloc_num_lb; lb_num++) {
981 				udf_bitmap_free(bitmap, *lmappos++, 1);
982 			}
983 			error = ENOSPC;
984 		}
985 		if (!error) {
986 			/* adjust freecount */
987 			lvid = ump->logvol_integrity;
988 			freepos = &lvid->tables[0] + vpart_num;
989 			free_lbs = udf_rw32(*freepos);
990 			*freepos = udf_rw32(free_lbs - num_lb);
991 		}
992 		break;
993 	case UDF_ALLOC_METABITMAP :		/* UDF 2.50, 2.60 BluRay-RE */
994 		/* allocate on metadata unallocated bits */
995 		alloc_num_lb = num_lb;
996 		bitmap = &ump->metadata_unalloc_bits;
997 		udf_bitmap_allocate(bitmap, is_node, &alloc_num_lb, lmappos);
998 		ump->lvclose |= UDF_WRITE_PART_BITMAPS;
999 
1000 		/* have we allocated all? */
1001 		if (alloc_num_lb) {
1002 			/* YIKES! TODO we need to extend the metadata partition */
1003 			/* free allocated piece for now */
1004 			lmappos = lmapping;
1005 			for (lb_num=0; lb_num < num_lb-alloc_num_lb; lb_num++) {
1006 				udf_bitmap_free(bitmap, *lmappos++, 1);
1007 			}
1008 			error = ENOSPC;
1009 		}
1010 		if (!error) {
1011 			/* adjust freecount */
1012 			lvid = ump->logvol_integrity;
1013 			freepos = &lvid->tables[0] + vpart_num;
1014 			free_lbs = udf_rw32(*freepos);
1015 			*freepos = udf_rw32(free_lbs - num_lb);
1016 		}
1017 		break;
1018 	case UDF_ALLOC_METASEQUENTIAL :		/* UDF 2.60       BluRay-R  */
1019 	case UDF_ALLOC_RELAXEDSEQUENTIAL :	/* UDF 2.50/~meta BluRay-R  */
1020 		printf("ALERT: udf_allocate_space : allocation %d "
1021 				"not implemented yet!\n", alloc_type);
1022 		/* TODO implement, doesn't have to be contiguous */
1023 		error = ENOSPC;
1024 		break;
1025 	}
1026 
1027 #ifdef DEBUG
1028 	if (udf_verbose & UDF_DEBUG_ALLOC) {
1029 		lmappos = lmapping;
1030 		printf("udf_allocate_space, allocated logical lba :\n");
1031 		for (lb_num = 0; lb_num < num_lb; lb_num++) {
1032 			printf("%s %"PRIu64",", (lb_num > 0)?",":"",
1033 				*lmappos++);
1034 		}
1035 		printf("\n");
1036 	}
1037 #endif
1038 	mutex_exit(&ump->allocate_mutex);
1039 
1040 	return error;
1041 }
1042 
1043 /* --------------------------------------------------------------------- */
1044 
1045 void
1046 udf_free_allocated_space(struct udf_mount *ump, uint32_t lb_num,
1047 	uint16_t vpart_num, uint32_t num_lb)
1048 {
1049 	struct udf_bitmap *bitmap;
1050 	struct part_desc *pdesc;
1051 	struct logvol_int_desc *lvid;
1052 	uint32_t ptov, lb_map, udf_rw32_lbmap;
1053 	uint32_t *freepos, free_lbs;
1054 	int phys_part;
1055 	int error;
1056 
1057 	DPRINTF(ALLOC, ("udf_free_allocated_space: freeing virt lbnum %d "
1058 			  "part %d + %d sect\n", lb_num, vpart_num, num_lb));
1059 
1060 	/* no use freeing zero length */
1061 	if (num_lb == 0)
1062 		return;
1063 
1064 	mutex_enter(&ump->allocate_mutex);
1065 
1066 	/* get partition backing up this vpart_num */
1067 	pdesc = ump->partitions[ump->vtop[vpart_num]];
1068 
1069 	switch (ump->vtop_tp[vpart_num]) {
1070 	case UDF_VTOP_TYPE_PHYS :
1071 	case UDF_VTOP_TYPE_SPARABLE :
1072 		/* free space to freed or unallocated space bitmap */
1073 		ptov      = udf_rw32(pdesc->start_loc);
1074 		phys_part = ump->vtop[vpart_num];
1075 
1076 		/* first try freed space bitmap */
1077 		bitmap    = &ump->part_freed_bits[phys_part];
1078 
1079 		/* if not defined, use unallocated bitmap */
1080 		if (bitmap->bits == NULL)
1081 			bitmap = &ump->part_unalloc_bits[phys_part];
1082 
1083 		/* if no bitmaps are defined, bail out; XXX OK? */
1084 		if (bitmap->bits == NULL)
1085 			break;
1086 
1087 		/* free bits if its defined */
1088 		KASSERT(bitmap->bits);
1089 		ump->lvclose |= UDF_WRITE_PART_BITMAPS;
1090 		udf_bitmap_free(bitmap, lb_num, num_lb);
1091 
1092 		/* adjust freecount */
1093 		lvid = ump->logvol_integrity;
1094 		freepos = &lvid->tables[0] + vpart_num;
1095 		free_lbs = udf_rw32(*freepos);
1096 		*freepos = udf_rw32(free_lbs + num_lb);
1097 		break;
1098 	case UDF_VTOP_TYPE_VIRT :
1099 		/* free this VAT entry */
1100 		KASSERT(num_lb == 1);
1101 
1102 		lb_map = 0xffffffff;
1103 		udf_rw32_lbmap = udf_rw32(lb_map);
1104 		error = udf_vat_write(ump->vat_node,
1105 			(uint8_t *) &udf_rw32_lbmap, 4,
1106 			ump->vat_offset + lb_num * 4);
1107 		KASSERT(error == 0);
1108 		ump->vat_last_free_lb = MIN(ump->vat_last_free_lb, lb_num);
1109 		break;
1110 	case UDF_VTOP_TYPE_META :
1111 		/* free space in the metadata bitmap */
1112 		bitmap = &ump->metadata_unalloc_bits;
1113 		KASSERT(bitmap->bits);
1114 
1115 		ump->lvclose |= UDF_WRITE_PART_BITMAPS;
1116 		udf_bitmap_free(bitmap, lb_num, num_lb);
1117 
1118 		/* adjust freecount */
1119 		lvid = ump->logvol_integrity;
1120 		freepos = &lvid->tables[0] + vpart_num;
1121 		free_lbs = udf_rw32(*freepos);
1122 		*freepos = udf_rw32(free_lbs + num_lb);
1123 		break;
1124 	default:
1125 		printf("ALERT: udf_free_allocated_space : allocation %d "
1126 			"not implemented yet!\n", ump->vtop_tp[vpart_num]);
1127 		break;
1128 	}
1129 
1130 	mutex_exit(&ump->allocate_mutex);
1131 }
1132 
1133 /* --------------------------------------------------------------------- */
1134 
1135 int
1136 udf_pre_allocate_space(struct udf_mount *ump, int udf_c_type,
1137 	uint32_t num_lb, uint16_t vpartnr, uint64_t *lmapping)
1138 {
1139 	/* TODO properly maintain uncomitted_lb per partition */
1140 
1141 	/* reserve size for VAT allocated data */
1142 	if (ump->vtop_alloc[vpartnr] == UDF_ALLOC_VAT) {
1143 		mutex_enter(&ump->allocate_mutex);
1144 			ump->uncomitted_lb += num_lb;
1145 		mutex_exit(&ump->allocate_mutex);
1146 	}
1147 
1148 	return udf_allocate_space(ump, udf_c_type, vpartnr, num_lb, lmapping);
1149 }
1150 
1151 /* --------------------------------------------------------------------- */
1152 
1153 /*
1154  * Allocate a buf on disc for direct write out. The space doesn't have to be
1155  * contiguous as the caller takes care of this.
1156  */
1157 
1158 void
1159 udf_late_allocate_buf(struct udf_mount *ump, struct buf *buf,
1160 	uint64_t *lmapping, struct long_ad *node_ad_cpy, uint16_t *vpart_nump)
1161 {
1162 	struct udf_node  *udf_node = VTOI(buf->b_vp);
1163 	int lb_size, blks, udf_c_type;
1164 	int vpart_num, num_lb;
1165 	int error, s;
1166 
1167 	/*
1168 	 * for each sector in the buf, allocate a sector on disc and record
1169 	 * its position in the provided mapping array.
1170 	 *
1171 	 * If its userdata or FIDs, record its location in its node.
1172 	 */
1173 
1174 	lb_size    = udf_rw32(ump->logical_vol->lb_size);
1175 	num_lb     = (buf->b_bcount + lb_size -1) / lb_size;
1176 	blks       = lb_size / DEV_BSIZE;
1177 	udf_c_type = buf->b_udf_c_type;
1178 
1179 	KASSERT(lb_size == ump->discinfo.sector_size);
1180 
1181 	/* select partition to record the buffer on */
1182 	vpart_num = ump->data_part;
1183 	if (udf_c_type == UDF_C_NODE)
1184 		vpart_num = ump->node_part;
1185 	if (udf_c_type == UDF_C_FIDS)
1186 		vpart_num = ump->fids_part;
1187 	*vpart_nump = vpart_num;
1188 
1189 	if (udf_c_type == UDF_C_NODE) {
1190 		/* if not VAT, its allready allocated */
1191 		if (ump->vtop_alloc[ump->node_part] != UDF_ALLOC_VAT)
1192 			return;
1193 
1194 		/* allocate on its backing sequential partition */
1195 		vpart_num = ump->data_part;
1196 	}
1197 
1198 	/* do allocation on the selected partition */
1199 	error = udf_allocate_space(ump, udf_c_type,
1200 			vpart_num, num_lb, lmapping);
1201 	if (error) {
1202 		/* ARGH! we've not done our accounting right! */
1203 		panic("UDF disc allocation accounting gone wrong");
1204 	}
1205 
1206 	/* commit our sector count */
1207 	mutex_enter(&ump->allocate_mutex);
1208 		if (num_lb > ump->uncomitted_lb) {
1209 			ump->uncomitted_lb = 0;
1210 		} else {
1211 			ump->uncomitted_lb -= num_lb;
1212 		}
1213 	mutex_exit(&ump->allocate_mutex);
1214 
1215 	/* If its userdata or FIDs, record its allocation in its node. */
1216 	if ((udf_c_type == UDF_C_USERDATA) ||
1217 	    (udf_c_type == UDF_C_FIDS) ||
1218 	    (udf_c_type == UDF_C_METADATA_SBM))
1219 	{
1220 		udf_record_allocation_in_node(ump, buf, vpart_num, lmapping,
1221 			node_ad_cpy);
1222 		/* decrement our outstanding bufs counter */
1223 		s = splbio();
1224 			udf_node->outstanding_bufs--;
1225 		splx(s);
1226 	}
1227 }
1228 
1229 /* --------------------------------------------------------------------- */
1230 
1231 /*
1232  * Try to merge a1 with the new piece a2. udf_ads_merge returns error when not
1233  * possible (anymore); a2 returns the rest piece.
1234  */
1235 
1236 static int
1237 udf_ads_merge(uint32_t lb_size, struct long_ad *a1, struct long_ad *a2)
1238 {
1239 	uint32_t max_len, merge_len;
1240 	uint32_t a1_len, a2_len;
1241 	uint32_t a1_flags, a2_flags;
1242 	uint32_t a1_lbnum, a2_lbnum;
1243 	uint16_t a1_part, a2_part;
1244 
1245 	max_len = ((UDF_EXT_MAXLEN / lb_size) * lb_size);
1246 
1247 	a1_flags = UDF_EXT_FLAGS(udf_rw32(a1->len));
1248 	a1_len   = UDF_EXT_LEN(udf_rw32(a1->len));
1249 	a1_lbnum = udf_rw32(a1->loc.lb_num);
1250 	a1_part  = udf_rw16(a1->loc.part_num);
1251 
1252 	a2_flags = UDF_EXT_FLAGS(udf_rw32(a2->len));
1253 	a2_len   = UDF_EXT_LEN(udf_rw32(a2->len));
1254 	a2_lbnum = udf_rw32(a2->loc.lb_num);
1255 	a2_part  = udf_rw16(a2->loc.part_num);
1256 
1257 	/* defines same space */
1258 	if (a1_flags != a2_flags)
1259 		return 1;
1260 
1261 	if (a1_flags != UDF_EXT_FREE) {
1262 		/* the same partition */
1263 		if (a1_part != a2_part)
1264 			return 1;
1265 
1266 		/* a2 is successor of a1 */
1267 		if (a1_lbnum * lb_size + a1_len != a2_lbnum * lb_size)
1268 			return 1;
1269 	}
1270 
1271 	/* merge as most from a2 if possible */
1272 	merge_len = MIN(a2_len, max_len - a1_len);
1273 	a1_len   += merge_len;
1274 	a2_len   -= merge_len;
1275 	a2_lbnum += merge_len/lb_size;
1276 
1277 	a1->len = udf_rw32(a1_len | a1_flags);
1278 	a2->len = udf_rw32(a2_len | a2_flags);
1279 	a2->loc.lb_num = udf_rw32(a2_lbnum);
1280 
1281 	if (a2_len > 0)
1282 		return 1;
1283 
1284 	/* there is space over to merge */
1285 	return 0;
1286 }
1287 
1288 /* --------------------------------------------------------------------- */
1289 
1290 static void
1291 udf_wipe_adslots(struct udf_node *udf_node)
1292 {
1293 	struct file_entry      *fe;
1294 	struct extfile_entry   *efe;
1295 	struct alloc_ext_entry *ext;
1296 	uint64_t inflen, objsize;
1297 	uint32_t lb_size, dscr_size, l_ea, l_ad, max_l_ad, crclen;
1298 	uint8_t *data_pos;
1299 	int extnr;
1300 
1301 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
1302 
1303 	fe  = udf_node->fe;
1304 	efe = udf_node->efe;
1305 	if (fe) {
1306 		inflen  = udf_rw64(fe->inf_len);
1307 		objsize = inflen;
1308 		dscr_size  = sizeof(struct file_entry) -1;
1309 		l_ea       = udf_rw32(fe->l_ea);
1310 		l_ad       = udf_rw32(fe->l_ad);
1311 		data_pos = (uint8_t *) fe + dscr_size + l_ea;
1312 	} else {
1313 		inflen  = udf_rw64(efe->inf_len);
1314 		objsize = udf_rw64(efe->obj_size);
1315 		dscr_size  = sizeof(struct extfile_entry) -1;
1316 		l_ea       = udf_rw32(efe->l_ea);
1317 		l_ad       = udf_rw32(efe->l_ad);
1318 		data_pos = (uint8_t *) efe + dscr_size + l_ea;
1319 	}
1320 	max_l_ad = lb_size - dscr_size - l_ea;
1321 
1322 	/* wipe fe/efe */
1323 	memset(data_pos, 0, max_l_ad);
1324 	crclen = dscr_size - UDF_DESC_TAG_LENGTH + l_ea;
1325 	if (fe) {
1326 		fe->l_ad         = udf_rw32(0);
1327 		fe->logblks_rec  = udf_rw64(0);
1328 		fe->tag.desc_crc_len = udf_rw16(crclen);
1329 	} else {
1330 		efe->l_ad        = udf_rw32(0);
1331 		efe->logblks_rec = udf_rw64(0);
1332 		efe->tag.desc_crc_len = udf_rw16(crclen);
1333 	}
1334 
1335 	/* wipe all allocation extent entries */
1336 	for (extnr = 0; extnr < udf_node->num_extensions; extnr++) {
1337 		ext = udf_node->ext[extnr];
1338 		dscr_size  = sizeof(struct alloc_ext_entry) -1;
1339 		data_pos = (uint8_t *) ext->data;
1340 		max_l_ad = lb_size - dscr_size;
1341 		memset(data_pos, 0, max_l_ad);
1342 		ext->l_ad = udf_rw32(0);
1343 
1344 		crclen = dscr_size - UDF_DESC_TAG_LENGTH;
1345 		ext->tag.desc_crc_len = udf_rw16(crclen);
1346 	}
1347 	udf_node->i_flags |= IN_NODE_REBUILD;
1348 }
1349 
1350 /* --------------------------------------------------------------------- */
1351 
1352 void
1353 udf_get_adslot(struct udf_node *udf_node, int slot, struct long_ad *icb,
1354 	int *eof) {
1355 	struct file_entry      *fe;
1356 	struct extfile_entry   *efe;
1357 	struct alloc_ext_entry *ext;
1358 	struct icb_tag *icbtag;
1359 	struct short_ad *short_ad;
1360 	struct long_ad *long_ad, l_icb;
1361 	uint32_t offset;
1362 	uint32_t lb_size, dscr_size, l_ea, l_ad, flags;
1363 	uint8_t *data_pos;
1364 	int icbflags, addr_type, adlen, extnr;
1365 
1366 	/* determine what descriptor we are in */
1367 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
1368 
1369 	fe  = udf_node->fe;
1370 	efe = udf_node->efe;
1371 	if (fe) {
1372 		icbtag  = &fe->icbtag;
1373 		dscr_size  = sizeof(struct file_entry) -1;
1374 		l_ea       = udf_rw32(fe->l_ea);
1375 		l_ad       = udf_rw32(fe->l_ad);
1376 		data_pos = (uint8_t *) fe + dscr_size + l_ea;
1377 	} else {
1378 		icbtag  = &efe->icbtag;
1379 		dscr_size  = sizeof(struct extfile_entry) -1;
1380 		l_ea       = udf_rw32(efe->l_ea);
1381 		l_ad       = udf_rw32(efe->l_ad);
1382 		data_pos = (uint8_t *) efe + dscr_size + l_ea;
1383 	}
1384 
1385 	icbflags  = udf_rw16(icbtag->flags);
1386 	addr_type = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
1387 
1388 	/* just in case we're called on an intern, its EOF */
1389 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
1390 		memset(icb, 0, sizeof(struct long_ad));
1391 		*eof = 1;
1392 		return;
1393 	}
1394 
1395 	adlen = 0;
1396 	if (addr_type == UDF_ICB_SHORT_ALLOC) {
1397 		adlen = sizeof(struct short_ad);
1398 	} else if (addr_type == UDF_ICB_LONG_ALLOC) {
1399 		adlen = sizeof(struct long_ad);
1400 	}
1401 
1402 	/* if offset too big, we go to the allocation extensions */
1403 	offset = slot * adlen;
1404 	extnr  = -1;
1405 	while (offset >= l_ad) {
1406 		/* check if our last entry is a redirect */
1407 		if (addr_type == UDF_ICB_SHORT_ALLOC) {
1408 			short_ad = (struct short_ad *) (data_pos + l_ad-adlen);
1409 			l_icb.len          = short_ad->len;
1410 			l_icb.loc.part_num = udf_node->loc.loc.part_num;
1411 			l_icb.loc.lb_num   = short_ad->lb_num;
1412 		} else {
1413 			KASSERT(addr_type == UDF_ICB_LONG_ALLOC);
1414 			long_ad = (struct long_ad *) (data_pos + l_ad-adlen);
1415 			l_icb = *long_ad;
1416 		}
1417 		flags = UDF_EXT_FLAGS(udf_rw32(l_icb.len));
1418 		if (flags != UDF_EXT_REDIRECT) {
1419 			l_ad = 0;	/* force EOF */
1420 			break;
1421 		}
1422 
1423 		/* advance to next extent */
1424 		extnr++;
1425 		if (extnr >= udf_node->num_extensions) {
1426 			l_ad = 0;	/* force EOF */
1427 			break;
1428 		}
1429 		offset = offset - l_ad;
1430 		ext  = udf_node->ext[extnr];
1431 		dscr_size  = sizeof(struct alloc_ext_entry) -1;
1432 		l_ad = udf_rw32(ext->l_ad);
1433 		data_pos = (uint8_t *) ext + dscr_size;
1434 	}
1435 
1436 	/* XXX l_ad == 0 should be enough to check */
1437 	*eof = (offset >= l_ad) || (l_ad == 0);
1438 	if (*eof) {
1439 		DPRINTF(PARANOIDADWLK, ("returning EOF, extnr %d, offset %d, "
1440 			"l_ad %d\n", extnr, offset, l_ad));
1441 		memset(icb, 0, sizeof(struct long_ad));
1442 		return;
1443 	}
1444 
1445 	/* get the element */
1446 	if (addr_type == UDF_ICB_SHORT_ALLOC) {
1447 		short_ad = (struct short_ad *) (data_pos + offset);
1448 		icb->len          = short_ad->len;
1449 		icb->loc.part_num = udf_node->loc.loc.part_num;
1450 		icb->loc.lb_num   = short_ad->lb_num;
1451 	} else if (addr_type == UDF_ICB_LONG_ALLOC) {
1452 		long_ad = (struct long_ad *) (data_pos + offset);
1453 		*icb = *long_ad;
1454 	}
1455 	DPRINTF(PARANOIDADWLK, ("returning element : v %d, lb %d, len %d, "
1456 		"flags %d\n", icb->loc.part_num, icb->loc.lb_num,
1457 		UDF_EXT_LEN(icb->len), UDF_EXT_FLAGS(icb->len)));
1458 }
1459 
1460 /* --------------------------------------------------------------------- */
1461 
1462 int
1463 udf_append_adslot(struct udf_node *udf_node, int *slot, struct long_ad *icb) {
1464 	struct udf_mount *ump = udf_node->ump;
1465 	union dscrptr          *dscr, *extdscr;
1466 	struct file_entry      *fe;
1467 	struct extfile_entry   *efe;
1468 	struct alloc_ext_entry *ext;
1469 	struct icb_tag *icbtag;
1470 	struct short_ad *short_ad;
1471 	struct long_ad *long_ad, o_icb, l_icb;
1472 	uint64_t logblks_rec, *logblks_rec_p;
1473 	uint64_t lmapping;
1474 	uint32_t offset, rest, len, lb_num;
1475 	uint32_t lb_size, dscr_size, l_ea, l_ad, *l_ad_p, max_l_ad, crclen;
1476 	uint32_t flags;
1477 	uint16_t vpart_num;
1478 	uint8_t *data_pos;
1479 	int icbflags, addr_type, adlen, extnr;
1480 	int error;
1481 
1482 	lb_size = udf_rw32(ump->logical_vol->lb_size);
1483 	vpart_num = udf_rw16(udf_node->loc.loc.part_num);
1484 
1485 	/* determine what descriptor we are in */
1486 	fe  = udf_node->fe;
1487 	efe = udf_node->efe;
1488 	if (fe) {
1489 		icbtag  = &fe->icbtag;
1490 		dscr      = (union dscrptr *) fe;
1491 		dscr_size = sizeof(struct file_entry) -1;
1492 
1493 		l_ea      = udf_rw32(fe->l_ea);
1494 		l_ad_p    = &fe->l_ad;
1495 		logblks_rec_p = &fe->logblks_rec;
1496 	} else {
1497 		icbtag    = &efe->icbtag;
1498 		dscr      = (union dscrptr *) efe;
1499 		dscr_size = sizeof(struct extfile_entry) -1;
1500 
1501 		l_ea      = udf_rw32(efe->l_ea);
1502 		l_ad_p    = &efe->l_ad;
1503 		logblks_rec_p = &efe->logblks_rec;
1504 	}
1505 	data_pos  = (uint8_t *) dscr + dscr_size + l_ea;
1506 	max_l_ad = lb_size - dscr_size - l_ea;
1507 
1508 	icbflags  = udf_rw16(icbtag->flags);
1509 	addr_type = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
1510 
1511 	/* just in case we're called on an intern, its EOF */
1512 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
1513 		panic("udf_append_adslot on UDF_ICB_INTERN_ALLOC\n");
1514 	}
1515 
1516 	adlen = 0;
1517 	if (addr_type == UDF_ICB_SHORT_ALLOC) {
1518 		adlen = sizeof(struct short_ad);
1519 	} else if (addr_type == UDF_ICB_LONG_ALLOC) {
1520 		adlen = sizeof(struct long_ad);
1521 	}
1522 
1523 	/* clean up given long_ad since it can be a synthesized one */
1524 	flags = UDF_EXT_FLAGS(udf_rw32(icb->len));
1525 	if (flags == UDF_EXT_FREE) {
1526 		icb->loc.part_num = udf_rw16(0);
1527 		icb->loc.lb_num   = udf_rw32(0);
1528 	}
1529 
1530 	/* if offset too big, we go to the allocation extensions */
1531 	l_ad   = udf_rw32(*l_ad_p);
1532 	offset = (*slot) * adlen;
1533 	extnr  = -1;
1534 	while (offset >= l_ad) {
1535 		/* check if our last entry is a redirect */
1536 		if (addr_type == UDF_ICB_SHORT_ALLOC) {
1537 			short_ad = (struct short_ad *) (data_pos + l_ad-adlen);
1538 			l_icb.len          = short_ad->len;
1539 			l_icb.loc.part_num = udf_node->loc.loc.part_num;
1540 			l_icb.loc.lb_num   = short_ad->lb_num;
1541 		} else {
1542 			KASSERT(addr_type == UDF_ICB_LONG_ALLOC);
1543 			long_ad = (struct long_ad *) (data_pos + l_ad-adlen);
1544 			l_icb = *long_ad;
1545 		}
1546 		flags = UDF_EXT_FLAGS(udf_rw32(l_icb.len));
1547 		if (flags != UDF_EXT_REDIRECT) {
1548 			/* only one past the last one is adressable */
1549 			break;
1550 		}
1551 
1552 		/* advance to next extent */
1553 		extnr++;
1554 		KASSERT(extnr < udf_node->num_extensions);
1555 		offset = offset - l_ad;
1556 
1557 		ext  = udf_node->ext[extnr];
1558 		dscr = (union dscrptr *) ext;
1559 		dscr_size  = sizeof(struct alloc_ext_entry) -1;
1560 		max_l_ad = lb_size - dscr_size;
1561 		l_ad_p = &ext->l_ad;
1562 		l_ad   = udf_rw32(*l_ad_p);
1563 		data_pos = (uint8_t *) ext + dscr_size;
1564 	}
1565 	DPRINTF(PARANOIDADWLK, ("append, ext %d, offset %d, l_ad %d\n",
1566 		extnr, offset, udf_rw32(*l_ad_p)));
1567 	KASSERT(l_ad == udf_rw32(*l_ad_p));
1568 
1569 	/* offset is offset within the current (E)FE/AED */
1570 	l_ad   = udf_rw32(*l_ad_p);
1571 	crclen = udf_rw16(dscr->tag.desc_crc_len);
1572 	logblks_rec = udf_rw64(*logblks_rec_p);
1573 
1574 	/* overwriting old piece? */
1575 	if (offset < l_ad) {
1576 		/* overwrite entry; compensate for the old element */
1577 		if (addr_type == UDF_ICB_SHORT_ALLOC) {
1578 			short_ad = (struct short_ad *) (data_pos + offset);
1579 			o_icb.len          = short_ad->len;
1580 			o_icb.loc.part_num = udf_rw16(0);	/* ignore */
1581 			o_icb.loc.lb_num   = short_ad->lb_num;
1582 		} else if (addr_type == UDF_ICB_LONG_ALLOC) {
1583 			long_ad = (struct long_ad *) (data_pos + offset);
1584 			o_icb = *long_ad;
1585 		} else {
1586 			panic("Invalid address type in udf_append_adslot\n");
1587 		}
1588 
1589 		len = udf_rw32(o_icb.len);
1590 		if (UDF_EXT_FLAGS(len) == UDF_EXT_ALLOCATED) {
1591 			/* adjust counts */
1592 			len = UDF_EXT_LEN(len);
1593 			logblks_rec -= (len + lb_size -1) / lb_size;
1594 		}
1595 	}
1596 
1597 	/* check if we're not appending a redirection */
1598 	flags = UDF_EXT_FLAGS(udf_rw32(icb->len));
1599 	KASSERT(flags != UDF_EXT_REDIRECT);
1600 
1601 	/* round down available space */
1602 	rest = adlen * ((max_l_ad - offset) / adlen);
1603 	if (rest <= adlen) {
1604 		/* have to append aed, see if we already have a spare one */
1605 		extnr++;
1606 		ext = udf_node->ext[extnr];
1607 		l_icb = udf_node->ext_loc[extnr];
1608 		if (ext == NULL) {
1609 			DPRINTF(ALLOC,("adding allocation extent %d\n", extnr));
1610 
1611 			error = udf_pre_allocate_space(ump, UDF_C_NODE, 1,
1612 					vpart_num, &lmapping);
1613 			lb_num = lmapping;
1614 			if (error)
1615 				return error;
1616 
1617 			/* initialise pointer to location */
1618 			memset(&l_icb, 0, sizeof(struct long_ad));
1619 			l_icb.len = udf_rw32(lb_size | UDF_EXT_REDIRECT);
1620 			l_icb.loc.lb_num   = udf_rw32(lb_num);
1621 			l_icb.loc.part_num = udf_rw16(vpart_num);
1622 
1623 			/* create new aed descriptor */
1624 			udf_create_logvol_dscr(ump, udf_node, &l_icb, &extdscr);
1625 			ext = &extdscr->aee;
1626 
1627 			udf_inittag(ump, &ext->tag, TAGID_ALLOCEXTENT, lb_num);
1628 			dscr_size  = sizeof(struct alloc_ext_entry) -1;
1629 			max_l_ad = lb_size - dscr_size;
1630 			memset(ext->data, 0, max_l_ad);
1631 			ext->l_ad = udf_rw32(0);
1632 			ext->tag.desc_crc_len =
1633 				udf_rw16(dscr_size - UDF_DESC_TAG_LENGTH);
1634 
1635 			/* declare aed */
1636 			udf_node->num_extensions++;
1637 			udf_node->ext_loc[extnr] = l_icb;
1638 			udf_node->ext[extnr] = ext;
1639 		}
1640 		/* add redirect and adjust l_ad and crclen for old descr */
1641 		if (addr_type == UDF_ICB_SHORT_ALLOC) {
1642 			short_ad = (struct short_ad *) (data_pos + offset);
1643 			short_ad->len    = l_icb.len;
1644 			short_ad->lb_num = l_icb.loc.lb_num;
1645 		} else if (addr_type == UDF_ICB_LONG_ALLOC) {
1646 			long_ad = (struct long_ad *) (data_pos + offset);
1647 			*long_ad = l_icb;
1648 		}
1649 		l_ad   += adlen;
1650 		crclen += adlen;
1651 		dscr->tag.desc_crc_len = udf_rw16(crclen);
1652 		*l_ad_p = udf_rw32(l_ad);
1653 
1654 		/* advance to the new extension */
1655 		KASSERT(ext != NULL);
1656 		dscr = (union dscrptr *) ext;
1657 		dscr_size  = sizeof(struct alloc_ext_entry) -1;
1658 		max_l_ad = lb_size - dscr_size;
1659 		data_pos = (uint8_t *) dscr + dscr_size;
1660 
1661 		l_ad_p = &ext->l_ad;
1662 		l_ad   = udf_rw32(*l_ad_p);
1663 		crclen = udf_rw16(dscr->tag.desc_crc_len);
1664 		offset = 0;
1665 
1666 		/* adjust callees slot count for link insert */
1667 		*slot += 1;
1668 	}
1669 
1670 	/* write out the element */
1671 	DPRINTF(PARANOIDADWLK, ("adding element : %p : v %d, lb %d, "
1672 			"len %d, flags %d\n", data_pos + offset,
1673 			icb->loc.part_num, icb->loc.lb_num,
1674 			UDF_EXT_LEN(icb->len), UDF_EXT_FLAGS(icb->len)));
1675 	if (addr_type == UDF_ICB_SHORT_ALLOC) {
1676 		short_ad = (struct short_ad *) (data_pos + offset);
1677 		short_ad->len    = icb->len;
1678 		short_ad->lb_num = icb->loc.lb_num;
1679 	} else if (addr_type == UDF_ICB_LONG_ALLOC) {
1680 		long_ad = (struct long_ad *) (data_pos + offset);
1681 		*long_ad = *icb;
1682 	}
1683 
1684 	/* adjust logblks recorded count */
1685 	len = udf_rw32(icb->len);
1686 	flags = UDF_EXT_FLAGS(len);
1687 	if (flags == UDF_EXT_ALLOCATED)
1688 		logblks_rec += (UDF_EXT_LEN(len) + lb_size -1) / lb_size;
1689 	*logblks_rec_p = udf_rw64(logblks_rec);
1690 
1691 	/* adjust l_ad and crclen when needed */
1692 	if (offset >= l_ad) {
1693 		l_ad   += adlen;
1694 		crclen += adlen;
1695 		dscr->tag.desc_crc_len = udf_rw16(crclen);
1696 		*l_ad_p = udf_rw32(l_ad);
1697 	}
1698 
1699 	return 0;
1700 }
1701 
1702 /* --------------------------------------------------------------------- */
1703 
1704 static void
1705 udf_count_alloc_exts(struct udf_node *udf_node)
1706 {
1707 	struct long_ad s_ad;
1708 	uint32_t lb_num, len, flags;
1709 	uint16_t vpart_num;
1710 	int slot, eof;
1711 	int num_extents, extnr;
1712 	int lb_size;
1713 
1714 	if (udf_node->num_extensions == 0)
1715 		return;
1716 
1717 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
1718 	/* count number of allocation extents in use */
1719 	num_extents = 0;
1720 	slot = 0;
1721 	for (;;) {
1722 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
1723 		if (eof)
1724 			break;
1725 		len   = udf_rw32(s_ad.len);
1726 		flags = UDF_EXT_FLAGS(len);
1727 
1728 		if (flags == UDF_EXT_REDIRECT)
1729 			num_extents++;
1730 
1731 		slot++;
1732 	}
1733 
1734 	DPRINTF(ALLOC, ("udf_count_alloc_ext counted %d live extents\n",
1735 		num_extents));
1736 
1737 	/* XXX choice: we could delay freeing them on node writeout */
1738 	/* free excess entries */
1739 	extnr = num_extents;
1740 	for (;extnr < udf_node->num_extensions; extnr++) {
1741 		DPRINTF(ALLOC, ("freeing alloc ext %d\n", extnr));
1742 		/* free dscriptor */
1743 		s_ad = udf_node->ext_loc[extnr];
1744 		udf_free_logvol_dscr(udf_node->ump, &s_ad,
1745 			udf_node->ext[extnr]);
1746 		udf_node->ext[extnr] = NULL;
1747 
1748 		/* free disc space */
1749 		lb_num    = udf_rw32(s_ad.loc.lb_num);
1750 		vpart_num = udf_rw16(s_ad.loc.part_num);
1751 		udf_free_allocated_space(udf_node->ump, lb_num, vpart_num, 1);
1752 
1753 		memset(&udf_node->ext_loc[extnr], 0, sizeof(struct long_ad));
1754 	}
1755 
1756 	/* set our new number of allocation extents */
1757 	udf_node->num_extensions = num_extents;
1758 }
1759 
1760 
1761 /* --------------------------------------------------------------------- */
1762 
1763 /*
1764  * Adjust the node's allocation descriptors to reflect the new mapping; do
1765  * take note that we might glue to existing allocation descriptors.
1766  *
1767  * XXX Note there can only be one allocation being recorded/mount; maybe
1768  * explicit allocation in shedule thread?
1769  */
1770 
1771 static void
1772 udf_record_allocation_in_node(struct udf_mount *ump, struct buf *buf,
1773 	uint16_t vpart_num, uint64_t *mapping, struct long_ad *node_ad_cpy)
1774 {
1775 	struct vnode    *vp = buf->b_vp;
1776 	struct udf_node *udf_node = VTOI(vp);
1777 	struct file_entry      *fe;
1778 	struct extfile_entry   *efe;
1779 	struct icb_tag  *icbtag;
1780 	struct long_ad   s_ad, c_ad;
1781 	uint64_t inflen, from, till;
1782 	uint64_t foffset, end_foffset, restart_foffset;
1783 	uint64_t orig_inflen, orig_lbrec, new_inflen, new_lbrec;
1784 	uint32_t num_lb, len, flags, lb_num;
1785 	uint32_t run_start;
1786 	uint32_t slot_offset, replace_len, replace;
1787 	int addr_type, icbflags;
1788 //	int udf_c_type = buf->b_udf_c_type;
1789 	int lb_size, run_length, eof;
1790 	int slot, cpy_slot, cpy_slots, restart_slot;
1791 	int error;
1792 
1793 	DPRINTF(ALLOC, ("udf_record_allocation_in_node\n"));
1794 
1795 #if 0
1796 	/* XXX disable sanity check for now */
1797 	/* sanity check ... should be panic ? */
1798 	if ((udf_c_type != UDF_C_USERDATA) && (udf_c_type != UDF_C_FIDS))
1799 		return;
1800 #endif
1801 
1802 	lb_size = udf_rw32(udf_node->ump->logical_vol->lb_size);
1803 
1804 	/* do the job */
1805 	UDF_LOCK_NODE(udf_node, 0);	/* XXX can deadlock ? */
1806 	udf_node_sanity_check(udf_node, &orig_inflen, &orig_lbrec);
1807 
1808 	fe  = udf_node->fe;
1809 	efe = udf_node->efe;
1810 	if (fe) {
1811 		icbtag = &fe->icbtag;
1812 		inflen = udf_rw64(fe->inf_len);
1813 	} else {
1814 		icbtag = &efe->icbtag;
1815 		inflen = udf_rw64(efe->inf_len);
1816 	}
1817 
1818 	/* do check if `till' is not past file information length */
1819 	from = buf->b_lblkno * lb_size;
1820 	till = MIN(inflen, from + buf->b_resid);
1821 
1822 	num_lb = (till - from + lb_size -1) / lb_size;
1823 
1824 	DPRINTF(ALLOC, ("record allocation from %"PRIu64" + %d\n", from, buf->b_bcount));
1825 
1826 	icbflags  = udf_rw16(icbtag->flags);
1827 	addr_type = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
1828 
1829 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
1830 		/* nothing to do */
1831 		/* XXX clean up rest of node? just in case? */
1832 		UDF_UNLOCK_NODE(udf_node, 0);
1833 		return;
1834 	}
1835 
1836 	slot     = 0;
1837 	cpy_slot = 0;
1838 	foffset  = 0;
1839 
1840 	/* 1) copy till first overlap piece to the rewrite buffer */
1841 	for (;;) {
1842 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
1843 		if (eof) {
1844 			DPRINTF(WRITE,
1845 				("Record allocation in node "
1846 				 "failed: encountered EOF\n"));
1847 			UDF_UNLOCK_NODE(udf_node, 0);
1848 			buf->b_error = EINVAL;
1849 			return;
1850 		}
1851 		len   = udf_rw32(s_ad.len);
1852 		flags = UDF_EXT_FLAGS(len);
1853 		len   = UDF_EXT_LEN(len);
1854 
1855 		if (flags == UDF_EXT_REDIRECT) {
1856 			slot++;
1857 			continue;
1858 		}
1859 
1860 		end_foffset = foffset + len;
1861 		if (end_foffset > from)
1862 			break;	/* found */
1863 
1864 		node_ad_cpy[cpy_slot++] = s_ad;
1865 
1866 		DPRINTF(ALLOC, ("\t1: vp %d, lb %d, len %d, flags %d "
1867 			"-> stack\n",
1868 			udf_rw16(s_ad.loc.part_num),
1869 			udf_rw32(s_ad.loc.lb_num),
1870 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
1871 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
1872 
1873 		foffset = end_foffset;
1874 		slot++;
1875 	}
1876 	restart_slot    = slot;
1877 	restart_foffset = foffset;
1878 
1879 	/* 2) trunc overlapping slot at overlap and copy it */
1880 	slot_offset = from - foffset;
1881 	if (slot_offset > 0) {
1882 		DPRINTF(ALLOC, ("\tslot_offset = %d, flags = %d (%d)\n",
1883 				slot_offset, flags >> 30, flags));
1884 
1885 		s_ad.len = udf_rw32(slot_offset | flags);
1886 		node_ad_cpy[cpy_slot++] = s_ad;
1887 
1888 		DPRINTF(ALLOC, ("\t2: vp %d, lb %d, len %d, flags %d "
1889 			"-> stack\n",
1890 			udf_rw16(s_ad.loc.part_num),
1891 			udf_rw32(s_ad.loc.lb_num),
1892 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
1893 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
1894 	}
1895 	foffset += slot_offset;
1896 
1897 	/* 3) insert new mappings */
1898 	memset(&s_ad, 0, sizeof(struct long_ad));
1899 	lb_num = 0;
1900 	for (lb_num = 0; lb_num < num_lb; lb_num++) {
1901 		run_start  = mapping[lb_num];
1902 		run_length = 1;
1903 		while (lb_num < num_lb-1) {
1904 			if (mapping[lb_num+1] != mapping[lb_num]+1)
1905 				if (mapping[lb_num+1] != mapping[lb_num])
1906 					break;
1907 			run_length++;
1908 			lb_num++;
1909 		}
1910 		/* insert slot for this mapping */
1911 		len = run_length * lb_size;
1912 
1913 		/* bounds checking */
1914 		if (foffset + len > till)
1915 			len = till - foffset;
1916 		KASSERT(foffset + len <= inflen);
1917 
1918 		s_ad.len = udf_rw32(len | UDF_EXT_ALLOCATED);
1919 		s_ad.loc.part_num = udf_rw16(vpart_num);
1920 		s_ad.loc.lb_num   = udf_rw32(run_start);
1921 
1922 		foffset += len;
1923 
1924 		/* paranoia */
1925 		if (len == 0) {
1926 			DPRINTF(WRITE,
1927 				("Record allocation in node "
1928 				 "failed: insert failed\n"));
1929 			UDF_UNLOCK_NODE(udf_node, 0);
1930 			buf->b_error = EINVAL;
1931 			return;
1932 		}
1933 		node_ad_cpy[cpy_slot++] = s_ad;
1934 
1935 		DPRINTF(ALLOC, ("\t3: insert new mapping vp %d lb %d, len %d, "
1936 				"flags %d -> stack\n",
1937 			udf_rw16(s_ad.loc.part_num), udf_rw32(s_ad.loc.lb_num),
1938 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
1939 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
1940 	}
1941 
1942 	/* 4) pop replaced length */
1943 	slot    = restart_slot;
1944 	foffset = restart_foffset;
1945 
1946 	replace_len = till - foffset;	/* total amount of bytes to pop */
1947 	slot_offset = from - foffset;	/* offset in first encounted slot */
1948 	KASSERT((slot_offset % lb_size) == 0);
1949 
1950 	for (;;) {
1951 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
1952 		if (eof)
1953 			break;
1954 
1955 		len    = udf_rw32(s_ad.len);
1956 		flags  = UDF_EXT_FLAGS(len);
1957 		len    = UDF_EXT_LEN(len);
1958 		lb_num = udf_rw32(s_ad.loc.lb_num);
1959 
1960 		if (flags == UDF_EXT_REDIRECT) {
1961 			slot++;
1962 			continue;
1963 		}
1964 
1965 		DPRINTF(ALLOC, ("\t4i: got slot %d, slot_offset %d, "
1966 				"replace_len %d, "
1967 				"vp %d, lb %d, len %d, flags %d\n",
1968 			slot, slot_offset, replace_len,
1969 			udf_rw16(s_ad.loc.part_num),
1970 			udf_rw32(s_ad.loc.lb_num),
1971 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
1972 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
1973 
1974 		/* adjust for slot offset */
1975 		if (slot_offset) {
1976 			DPRINTF(ALLOC, ("\t4s: skipping %d\n", slot_offset));
1977 			lb_num += slot_offset / lb_size;
1978 			len    -= slot_offset;
1979 			foffset += slot_offset;
1980 			replace_len -= slot_offset;
1981 
1982 			/* mark adjusted */
1983 			slot_offset = 0;
1984 		}
1985 
1986 		/* advance for (the rest of) this slot */
1987 		replace = MIN(len, replace_len);
1988 		DPRINTF(ALLOC, ("\t4d: replacing %d\n", replace));
1989 
1990 		/* advance for this slot */
1991 		if (replace) {
1992 			/* note: dont round DOWN on num_lb since we then
1993 			 * forget the last partial one */
1994 			num_lb = (replace + lb_size - 1) / lb_size;
1995 			if (flags != UDF_EXT_FREE) {
1996 				udf_free_allocated_space(ump, lb_num,
1997 					udf_rw16(s_ad.loc.part_num), num_lb);
1998 			}
1999 			lb_num      += num_lb;
2000 			len         -= replace;
2001 			foffset     += replace;
2002 			replace_len -= replace;
2003 		}
2004 
2005 		/* do we have a slot tail ? */
2006 		if (len) {
2007 			KASSERT(foffset % lb_size == 0);
2008 
2009 			/* we arrived at our point, push remainder */
2010 			s_ad.len        = udf_rw32(len | flags);
2011 			s_ad.loc.lb_num = udf_rw32(lb_num);
2012 			if (flags == UDF_EXT_FREE)
2013 				s_ad.loc.lb_num = udf_rw32(0);
2014 			node_ad_cpy[cpy_slot++] = s_ad;
2015 			foffset += len;
2016 			slot++;
2017 
2018 			DPRINTF(ALLOC, ("\t4: vp %d, lb %d, len %d, flags %d "
2019 				"-> stack\n",
2020 				udf_rw16(s_ad.loc.part_num),
2021 				udf_rw32(s_ad.loc.lb_num),
2022 				UDF_EXT_LEN(udf_rw32(s_ad.len)),
2023 				UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2024 			break;
2025 		}
2026 
2027 		slot++;
2028 	}
2029 
2030 	/* 5) copy remainder */
2031 	for (;;) {
2032 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
2033 		if (eof)
2034 			break;
2035 
2036 		len   = udf_rw32(s_ad.len);
2037 		flags = UDF_EXT_FLAGS(len);
2038 		len   = UDF_EXT_LEN(len);
2039 
2040 		if (flags == UDF_EXT_REDIRECT) {
2041 			slot++;
2042 			continue;
2043 		}
2044 
2045 		node_ad_cpy[cpy_slot++] = s_ad;
2046 
2047 		DPRINTF(ALLOC, ("\t5: insert new mapping "
2048 			"vp %d lb %d, len %d, flags %d "
2049 			"-> stack\n",
2050 		udf_rw16(s_ad.loc.part_num),
2051 		udf_rw32(s_ad.loc.lb_num),
2052 		UDF_EXT_LEN(udf_rw32(s_ad.len)),
2053 		UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2054 
2055 		slot++;
2056 	}
2057 
2058 	/* 6) reset node descriptors */
2059 	udf_wipe_adslots(udf_node);
2060 
2061 	/* 7) copy back extents; merge when possible. Recounting on the fly */
2062 	cpy_slots = cpy_slot;
2063 
2064 	c_ad = node_ad_cpy[0];
2065 	slot = 0;
2066 	DPRINTF(ALLOC, ("\t7s: stack -> got mapping vp %d "
2067 		"lb %d, len %d, flags %d\n",
2068 	udf_rw16(c_ad.loc.part_num),
2069 	udf_rw32(c_ad.loc.lb_num),
2070 	UDF_EXT_LEN(udf_rw32(c_ad.len)),
2071 	UDF_EXT_FLAGS(udf_rw32(c_ad.len)) >> 30));
2072 
2073 	for (cpy_slot = 1; cpy_slot < cpy_slots; cpy_slot++) {
2074 		s_ad = node_ad_cpy[cpy_slot];
2075 
2076 		DPRINTF(ALLOC, ("\t7i: stack -> got mapping vp %d "
2077 			"lb %d, len %d, flags %d\n",
2078 		udf_rw16(s_ad.loc.part_num),
2079 		udf_rw32(s_ad.loc.lb_num),
2080 		UDF_EXT_LEN(udf_rw32(s_ad.len)),
2081 		UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2082 
2083 		/* see if we can merge */
2084 		if (udf_ads_merge(lb_size, &c_ad, &s_ad)) {
2085 			/* not mergable (anymore) */
2086 			DPRINTF(ALLOC, ("\t7: appending vp %d lb %d, "
2087 				"len %d, flags %d\n",
2088 			udf_rw16(c_ad.loc.part_num),
2089 			udf_rw32(c_ad.loc.lb_num),
2090 			UDF_EXT_LEN(udf_rw32(c_ad.len)),
2091 			UDF_EXT_FLAGS(udf_rw32(c_ad.len)) >> 30));
2092 
2093 			error = udf_append_adslot(udf_node, &slot, &c_ad);
2094 			if (error) {
2095 				buf->b_error = error;
2096 				goto out;
2097 			}
2098 			c_ad = s_ad;
2099 			slot++;
2100 		}
2101 	}
2102 
2103 	/* 8) push rest slot (if any) */
2104 	if (UDF_EXT_LEN(c_ad.len) > 0) {
2105 		DPRINTF(ALLOC, ("\t8: last append vp %d lb %d, "
2106 				"len %d, flags %d\n",
2107 		udf_rw16(c_ad.loc.part_num),
2108 		udf_rw32(c_ad.loc.lb_num),
2109 		UDF_EXT_LEN(udf_rw32(c_ad.len)),
2110 		UDF_EXT_FLAGS(udf_rw32(c_ad.len)) >> 30));
2111 
2112 		error = udf_append_adslot(udf_node, &slot, &c_ad);
2113 		if (error) {
2114 			buf->b_error = error;
2115 			goto out;
2116 		}
2117 	}
2118 
2119 out:
2120 	udf_count_alloc_exts(udf_node);
2121 
2122 	/* the node's descriptors should now be sane */
2123 	udf_node_sanity_check(udf_node, &new_inflen, &new_lbrec);
2124 	UDF_UNLOCK_NODE(udf_node, 0);
2125 
2126 	KASSERT(orig_inflen == new_inflen);
2127 	KASSERT(new_lbrec >= orig_lbrec);
2128 
2129 	return;
2130 }
2131 
2132 /* --------------------------------------------------------------------- */
2133 
2134 int
2135 udf_grow_node(struct udf_node *udf_node, uint64_t new_size)
2136 {
2137 	union dscrptr *dscr;
2138 	struct vnode *vp = udf_node->vnode;
2139 	struct udf_mount *ump = udf_node->ump;
2140 	struct file_entry    *fe;
2141 	struct extfile_entry *efe;
2142 	struct icb_tag  *icbtag;
2143 	struct long_ad c_ad, s_ad;
2144 	uint64_t size_diff, old_size, inflen, objsize, chunk, append_len;
2145 	uint64_t foffset, end_foffset;
2146 	uint64_t orig_inflen, orig_lbrec, new_inflen, new_lbrec;
2147 	uint32_t lb_size, dscr_size, crclen, lastblock_grow;
2148 	uint32_t icbflags, len, flags, max_len;
2149 	uint32_t max_l_ad, l_ad, l_ea;
2150 	uint16_t my_part, dst_part;
2151 	uint8_t *data_pos, *evacuated_data;
2152 	int addr_type;
2153 	int slot, cpy_slot;
2154 	int isdir, eof, error;
2155 
2156 	DPRINTF(ALLOC, ("udf_grow_node\n"));
2157 
2158 	UDF_LOCK_NODE(udf_node, 0);
2159 	udf_node_sanity_check(udf_node, &orig_inflen, &orig_lbrec);
2160 
2161 	lb_size = udf_rw32(ump->logical_vol->lb_size);
2162 	max_len = ((UDF_EXT_MAXLEN / lb_size) * lb_size);
2163 
2164 	fe  = udf_node->fe;
2165 	efe = udf_node->efe;
2166 	if (fe) {
2167 		dscr       = (union dscrptr *) fe;
2168 		icbtag  = &fe->icbtag;
2169 		inflen  = udf_rw64(fe->inf_len);
2170 		objsize = inflen;
2171 		dscr_size  = sizeof(struct file_entry) -1;
2172 		l_ea       = udf_rw32(fe->l_ea);
2173 		l_ad       = udf_rw32(fe->l_ad);
2174 	} else {
2175 		dscr       = (union dscrptr *) efe;
2176 		icbtag  = &efe->icbtag;
2177 		inflen  = udf_rw64(efe->inf_len);
2178 		objsize = udf_rw64(efe->obj_size);
2179 		dscr_size  = sizeof(struct extfile_entry) -1;
2180 		l_ea       = udf_rw32(efe->l_ea);
2181 		l_ad       = udf_rw32(efe->l_ad);
2182 	}
2183 	data_pos  = (uint8_t *) dscr + dscr_size + l_ea;
2184 	max_l_ad = lb_size - dscr_size - l_ea;
2185 
2186 	icbflags   = udf_rw16(icbtag->flags);
2187 	addr_type  = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
2188 
2189 	old_size  = inflen;
2190 	size_diff = new_size - old_size;
2191 
2192 	DPRINTF(ALLOC, ("\tfrom %"PRIu64" to %"PRIu64"\n", old_size, new_size));
2193 
2194 	evacuated_data = NULL;
2195 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
2196 		if (l_ad + size_diff <= max_l_ad) {
2197 			/* only reflect size change directly in the node */
2198 			inflen  += size_diff;
2199 			objsize += size_diff;
2200 			l_ad    += size_diff;
2201 			crclen = dscr_size - UDF_DESC_TAG_LENGTH + l_ea + l_ad;
2202 			if (fe) {
2203 				fe->inf_len   = udf_rw64(inflen);
2204 				fe->l_ad      = udf_rw32(l_ad);
2205 				fe->tag.desc_crc_len = udf_rw16(crclen);
2206 			} else {
2207 				efe->inf_len  = udf_rw64(inflen);
2208 				efe->obj_size = udf_rw64(objsize);
2209 				efe->l_ad     = udf_rw32(l_ad);
2210 				efe->tag.desc_crc_len = udf_rw16(crclen);
2211 			}
2212 			error = 0;
2213 
2214 			/* set new size for uvm */
2215 			uvm_vnp_setsize(vp, old_size);
2216 			uvm_vnp_setwritesize(vp, new_size);
2217 
2218 #if 0
2219 			/* zero append space in buffer */
2220 			uvm_vnp_zerorange(vp, old_size, new_size - old_size);
2221 #endif
2222 
2223 			udf_node_sanity_check(udf_node, &new_inflen, &new_lbrec);
2224 
2225 			/* unlock */
2226 			UDF_UNLOCK_NODE(udf_node, 0);
2227 
2228 			KASSERT(new_inflen == orig_inflen + size_diff);
2229 			KASSERT(new_lbrec == orig_lbrec);
2230 			KASSERT(new_lbrec == 0);
2231 			return 0;
2232 		}
2233 
2234 		DPRINTF(ALLOC, ("\tCONVERT from internal\n"));
2235 
2236 		if (old_size > 0) {
2237 			/* allocate some space and copy in the stuff to keep */
2238 			evacuated_data = malloc(lb_size, M_UDFTEMP, M_WAITOK);
2239 			memset(evacuated_data, 0, lb_size);
2240 
2241 			/* node is locked, so safe to exit mutex */
2242 			UDF_UNLOCK_NODE(udf_node, 0);
2243 
2244 			/* read in using the `normal' vn_rdwr() */
2245 			error = vn_rdwr(UIO_READ, udf_node->vnode,
2246 					evacuated_data, old_size, 0,
2247 					UIO_SYSSPACE, IO_ALTSEMANTICS | IO_NODELOCKED,
2248 					FSCRED, NULL, NULL);
2249 
2250 			/* enter again */
2251 			UDF_LOCK_NODE(udf_node, 0);
2252 		}
2253 
2254 		/* convert to a normal alloc and select type */
2255 		isdir    = (vp->v_type == VDIR);
2256 		my_part  = udf_rw16(udf_node->loc.loc.part_num);
2257 		dst_part = isdir? ump->fids_part : ump->data_part;
2258 		addr_type = UDF_ICB_SHORT_ALLOC;
2259 		if (dst_part != my_part)
2260 			addr_type = UDF_ICB_LONG_ALLOC;
2261 
2262 		icbflags &= ~UDF_ICB_TAG_FLAGS_ALLOC_MASK;
2263 		icbflags |= addr_type;
2264 		icbtag->flags = udf_rw16(icbflags);
2265 
2266 		/* wipe old descriptor space */
2267 		udf_wipe_adslots(udf_node);
2268 
2269 		memset(&c_ad, 0, sizeof(struct long_ad));
2270 		c_ad.len          = udf_rw32(old_size | UDF_EXT_FREE);
2271 		c_ad.loc.part_num = udf_rw16(0); /* not relevant */
2272 		c_ad.loc.lb_num   = udf_rw32(0); /* not relevant */
2273 
2274 		slot = 0;
2275 	} else {
2276 		/* goto the last entry (if any) */
2277 		slot     = 0;
2278 		cpy_slot = 0;
2279 		foffset  = 0;
2280 		memset(&c_ad, 0, sizeof(struct long_ad));
2281 		for (;;) {
2282 			udf_get_adslot(udf_node, slot, &c_ad, &eof);
2283 			if (eof)
2284 				break;
2285 
2286 			len   = udf_rw32(c_ad.len);
2287 			flags = UDF_EXT_FLAGS(len);
2288 			len   = UDF_EXT_LEN(len);
2289 
2290 			end_foffset = foffset + len;
2291 			if (flags != UDF_EXT_REDIRECT)
2292 				foffset = end_foffset;
2293 
2294 			slot++;
2295 		}
2296 		/* at end of adslots */
2297 
2298 		/* special case if the old size was zero, then there is no last slot */
2299 		if (old_size == 0) {
2300 			c_ad.len          = udf_rw32(0 | UDF_EXT_FREE);
2301 			c_ad.loc.part_num = udf_rw16(0); /* not relevant */
2302 			c_ad.loc.lb_num   = udf_rw32(0); /* not relevant */
2303 		} else {
2304 			/* refetch last slot */
2305 			slot--;
2306 			udf_get_adslot(udf_node, slot, &c_ad, &eof);
2307 		}
2308 	}
2309 
2310 	/*
2311 	 * If the length of the last slot is not a multiple of lb_size, adjust
2312 	 * length so that it is; don't forget to adjust `append_len'! relevant for
2313 	 * extending existing files
2314 	 */
2315 	len   = udf_rw32(c_ad.len);
2316 	flags = UDF_EXT_FLAGS(len);
2317 	len   = UDF_EXT_LEN(len);
2318 
2319 	lastblock_grow = 0;
2320 	if (len % lb_size > 0) {
2321 		lastblock_grow = lb_size - (len % lb_size);
2322 		lastblock_grow = MIN(size_diff, lastblock_grow);
2323 		len += lastblock_grow;
2324 		c_ad.len = udf_rw32(len | flags);
2325 
2326 		/* TODO zero appened space in buffer! */
2327 		/* using uvm_vnp_zerorange(vp, old_size, new_size - old_size); ? */
2328 	}
2329 	memset(&s_ad, 0, sizeof(struct long_ad));
2330 
2331 	/* size_diff can be bigger than allowed, so grow in chunks */
2332 	append_len = size_diff - lastblock_grow;
2333 	while (append_len > 0) {
2334 		chunk = MIN(append_len, max_len);
2335 		s_ad.len = udf_rw32(chunk | UDF_EXT_FREE);
2336 		s_ad.loc.part_num = udf_rw16(0);
2337 		s_ad.loc.lb_num   = udf_rw32(0);
2338 
2339 		if (udf_ads_merge(lb_size, &c_ad, &s_ad)) {
2340 			/* not mergable (anymore) */
2341 			error = udf_append_adslot(udf_node, &slot, &c_ad);
2342 			if (error)
2343 				goto errorout;
2344 			slot++;
2345 			c_ad = s_ad;
2346 			memset(&s_ad, 0, sizeof(struct long_ad));
2347 		}
2348 		append_len -= chunk;
2349 	}
2350 
2351 	/* if there is a rest piece in the accumulator, append it */
2352 	if (UDF_EXT_LEN(udf_rw32(c_ad.len)) > 0) {
2353 		error = udf_append_adslot(udf_node, &slot, &c_ad);
2354 		if (error)
2355 			goto errorout;
2356 		slot++;
2357 	}
2358 
2359 	/* if there is a rest piece that didn't fit, append it */
2360 	if (UDF_EXT_LEN(udf_rw32(s_ad.len)) > 0) {
2361 		error = udf_append_adslot(udf_node, &slot, &s_ad);
2362 		if (error)
2363 			goto errorout;
2364 		slot++;
2365 	}
2366 
2367 	inflen  += size_diff;
2368 	objsize += size_diff;
2369 	if (fe) {
2370 		fe->inf_len   = udf_rw64(inflen);
2371 	} else {
2372 		efe->inf_len  = udf_rw64(inflen);
2373 		efe->obj_size = udf_rw64(objsize);
2374 	}
2375 	error = 0;
2376 
2377 	if (evacuated_data) {
2378 		/* set new write size for uvm */
2379 		uvm_vnp_setwritesize(vp, old_size);
2380 
2381 		/* write out evacuated data */
2382 		error = vn_rdwr(UIO_WRITE, udf_node->vnode,
2383 				evacuated_data, old_size, 0,
2384 				UIO_SYSSPACE, IO_ALTSEMANTICS | IO_NODELOCKED,
2385 				FSCRED, NULL, NULL);
2386 		uvm_vnp_setsize(vp, old_size);
2387 	}
2388 
2389 errorout:
2390 	if (evacuated_data)
2391 		free(evacuated_data, M_UDFTEMP);
2392 
2393 	udf_count_alloc_exts(udf_node);
2394 
2395 	udf_node_sanity_check(udf_node, &new_inflen, &new_lbrec);
2396 	UDF_UNLOCK_NODE(udf_node, 0);
2397 
2398 	KASSERT(new_inflen == orig_inflen + size_diff);
2399 	KASSERT(new_lbrec == orig_lbrec);
2400 
2401 	return error;
2402 }
2403 
2404 /* --------------------------------------------------------------------- */
2405 
2406 int
2407 udf_shrink_node(struct udf_node *udf_node, uint64_t new_size)
2408 {
2409 	struct vnode *vp = udf_node->vnode;
2410 	struct udf_mount *ump = udf_node->ump;
2411 	struct file_entry    *fe;
2412 	struct extfile_entry *efe;
2413 	struct icb_tag  *icbtag;
2414 	struct long_ad c_ad, s_ad, *node_ad_cpy;
2415 	uint64_t size_diff, old_size, inflen, objsize;
2416 	uint64_t foffset, end_foffset;
2417 	uint64_t orig_inflen, orig_lbrec, new_inflen, new_lbrec;
2418 	uint32_t lb_size, dscr_size, crclen;
2419 	uint32_t slot_offset;
2420 	uint32_t len, flags, max_len;
2421 	uint32_t num_lb, lb_num;
2422 	uint32_t max_l_ad, l_ad, l_ea;
2423 	uint16_t vpart_num;
2424 	uint8_t *data_pos;
2425 	int icbflags, addr_type;
2426 	int slot, cpy_slot, cpy_slots;
2427 	int eof, error;
2428 
2429 	DPRINTF(ALLOC, ("udf_shrink_node\n"));
2430 
2431 	UDF_LOCK_NODE(udf_node, 0);
2432 	udf_node_sanity_check(udf_node, &orig_inflen, &orig_lbrec);
2433 
2434 	lb_size = udf_rw32(ump->logical_vol->lb_size);
2435 	max_len = ((UDF_EXT_MAXLEN / lb_size) * lb_size);
2436 
2437 	/* do the work */
2438 	fe  = udf_node->fe;
2439 	efe = udf_node->efe;
2440 	if (fe) {
2441 		icbtag  = &fe->icbtag;
2442 		inflen  = udf_rw64(fe->inf_len);
2443 		objsize = inflen;
2444 		dscr_size  = sizeof(struct file_entry) -1;
2445 		l_ea       = udf_rw32(fe->l_ea);
2446 		l_ad       = udf_rw32(fe->l_ad);
2447 		data_pos = (uint8_t *) fe + dscr_size + l_ea;
2448 	} else {
2449 		icbtag  = &efe->icbtag;
2450 		inflen  = udf_rw64(efe->inf_len);
2451 		objsize = udf_rw64(efe->obj_size);
2452 		dscr_size  = sizeof(struct extfile_entry) -1;
2453 		l_ea       = udf_rw32(efe->l_ea);
2454 		l_ad       = udf_rw32(efe->l_ad);
2455 		data_pos = (uint8_t *) efe + dscr_size + l_ea;
2456 	}
2457 	max_l_ad = lb_size - dscr_size - l_ea;
2458 
2459 	icbflags   = udf_rw16(icbtag->flags);
2460 	addr_type  = icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
2461 
2462 	old_size  = inflen;
2463 	size_diff = old_size - new_size;
2464 
2465 	DPRINTF(ALLOC, ("\tfrom %"PRIu64" to %"PRIu64"\n", old_size, new_size));
2466 
2467 	/* shrink the node to its new size */
2468 	if (addr_type == UDF_ICB_INTERN_ALLOC) {
2469 		/* only reflect size change directly in the node */
2470 		KASSERT(new_size <= max_l_ad);
2471 		inflen  -= size_diff;
2472 		objsize -= size_diff;
2473 		l_ad    -= size_diff;
2474 		crclen = dscr_size - UDF_DESC_TAG_LENGTH + l_ea + l_ad;
2475 		if (fe) {
2476 			fe->inf_len   = udf_rw64(inflen);
2477 			fe->l_ad      = udf_rw32(l_ad);
2478 			fe->tag.desc_crc_len = udf_rw16(crclen);
2479 		} else {
2480 			efe->inf_len  = udf_rw64(inflen);
2481 			efe->obj_size = udf_rw64(objsize);
2482 			efe->l_ad     = udf_rw32(l_ad);
2483 			efe->tag.desc_crc_len = udf_rw16(crclen);
2484 		}
2485 		error = 0;
2486 
2487 		/* clear the space in the descriptor */
2488 		KASSERT(old_size > new_size);
2489 		memset(data_pos + new_size, 0, old_size - new_size);
2490 
2491 		/* TODO zero appened space in buffer! */
2492 		/* using uvm_vnp_zerorange(vp, old_size, old_size - new_size); ? */
2493 
2494 		/* set new size for uvm */
2495 		uvm_vnp_setsize(vp, new_size);
2496 
2497 		udf_node_sanity_check(udf_node, &new_inflen, &new_lbrec);
2498 		UDF_UNLOCK_NODE(udf_node, 0);
2499 
2500 		KASSERT(new_inflen == orig_inflen - size_diff);
2501 		KASSERT(new_lbrec == orig_lbrec);
2502 		KASSERT(new_lbrec == 0);
2503 
2504 		return 0;
2505 	}
2506 
2507 	/* setup node cleanup extents copy space */
2508 	node_ad_cpy = malloc(lb_size * UDF_MAX_ALLOC_EXTENTS,
2509 		M_UDFMNT, M_WAITOK);
2510 	memset(node_ad_cpy, 0, lb_size * UDF_MAX_ALLOC_EXTENTS);
2511 
2512 	/*
2513 	 * Shrink the node by releasing the allocations and truncate the last
2514 	 * allocation to the new size. If the new size fits into the
2515 	 * allocation descriptor itself, transform it into an
2516 	 * UDF_ICB_INTERN_ALLOC.
2517 	 */
2518 	slot     = 0;
2519 	cpy_slot = 0;
2520 	foffset  = 0;
2521 
2522 	/* 1) copy till first overlap piece to the rewrite buffer */
2523 	for (;;) {
2524 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
2525 		if (eof) {
2526 			DPRINTF(WRITE,
2527 				("Shrink node failed: "
2528 				 "encountered EOF\n"));
2529 			error = EINVAL;
2530 			goto errorout; /* panic? */
2531 		}
2532 		len   = udf_rw32(s_ad.len);
2533 		flags = UDF_EXT_FLAGS(len);
2534 		len   = UDF_EXT_LEN(len);
2535 
2536 		if (flags == UDF_EXT_REDIRECT) {
2537 			slot++;
2538 			continue;
2539 		}
2540 
2541 		end_foffset = foffset + len;
2542 		if (end_foffset > new_size)
2543 			break;	/* found */
2544 
2545 		node_ad_cpy[cpy_slot++] = s_ad;
2546 
2547 		DPRINTF(ALLOC, ("\t1: vp %d, lb %d, len %d, flags %d "
2548 			"-> stack\n",
2549 			udf_rw16(s_ad.loc.part_num),
2550 			udf_rw32(s_ad.loc.lb_num),
2551 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
2552 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2553 
2554 		foffset = end_foffset;
2555 		slot++;
2556 	}
2557 	slot_offset = new_size - foffset;
2558 
2559 	/* 2) trunc overlapping slot at overlap and copy it */
2560 	if (slot_offset > 0) {
2561 		lb_num    = udf_rw32(s_ad.loc.lb_num);
2562 		vpart_num = udf_rw16(s_ad.loc.part_num);
2563 
2564 		if (flags == UDF_EXT_ALLOCATED) {
2565 			/* note: round DOWN on num_lb */
2566 			lb_num += (slot_offset + lb_size -1) / lb_size;
2567 			num_lb  = (len - slot_offset) / lb_size;
2568 
2569 			udf_free_allocated_space(ump, lb_num, vpart_num, num_lb);
2570 		}
2571 
2572 		s_ad.len = udf_rw32(slot_offset | flags);
2573 		node_ad_cpy[cpy_slot++] = s_ad;
2574 		slot++;
2575 
2576 		DPRINTF(ALLOC, ("\t2: vp %d, lb %d, len %d, flags %d "
2577 			"-> stack\n",
2578 			udf_rw16(s_ad.loc.part_num),
2579 			udf_rw32(s_ad.loc.lb_num),
2580 			UDF_EXT_LEN(udf_rw32(s_ad.len)),
2581 			UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2582 	}
2583 
2584 	/* 3) delete remainder */
2585 	for (;;) {
2586 		udf_get_adslot(udf_node, slot, &s_ad, &eof);
2587 		if (eof)
2588 			break;
2589 
2590 		len       = udf_rw32(s_ad.len);
2591 		flags     = UDF_EXT_FLAGS(len);
2592 		len       = UDF_EXT_LEN(len);
2593 
2594 		if (flags == UDF_EXT_REDIRECT) {
2595 			slot++;
2596 			continue;
2597 		}
2598 
2599 		DPRINTF(ALLOC, ("\t3: delete remainder "
2600 			"vp %d lb %d, len %d, flags %d\n",
2601 		udf_rw16(s_ad.loc.part_num),
2602 		udf_rw32(s_ad.loc.lb_num),
2603 		UDF_EXT_LEN(udf_rw32(s_ad.len)),
2604 		UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2605 
2606 		if (flags == UDF_EXT_ALLOCATED) {
2607 			lb_num    = udf_rw32(s_ad.loc.lb_num);
2608 			vpart_num = udf_rw16(s_ad.loc.part_num);
2609 			num_lb    = (len + lb_size - 1) / lb_size;
2610 
2611 			udf_free_allocated_space(ump, lb_num, vpart_num,
2612 				num_lb);
2613 		}
2614 
2615 		slot++;
2616 	}
2617 
2618 	/* 4) if it will fit into the descriptor then convert */
2619 	if (new_size < max_l_ad) {
2620 		/*
2621 		 * resque/evacuate old piece by reading it in, and convert it
2622 		 * to internal alloc.
2623 		 */
2624 		if (new_size == 0) {
2625 			/* XXX/TODO only for zero sizing now */
2626 			udf_wipe_adslots(udf_node);
2627 
2628 			icbflags &= ~UDF_ICB_TAG_FLAGS_ALLOC_MASK;
2629 			icbflags |=  UDF_ICB_INTERN_ALLOC;
2630 			icbtag->flags = udf_rw16(icbflags);
2631 
2632 			inflen  -= size_diff;	KASSERT(inflen == 0);
2633 			objsize -= size_diff;
2634 			l_ad     = new_size;
2635 			crclen = dscr_size - UDF_DESC_TAG_LENGTH + l_ea + l_ad;
2636 			if (fe) {
2637 				fe->inf_len   = udf_rw64(inflen);
2638 				fe->l_ad      = udf_rw32(l_ad);
2639 				fe->tag.desc_crc_len = udf_rw16(crclen);
2640 			} else {
2641 				efe->inf_len  = udf_rw64(inflen);
2642 				efe->obj_size = udf_rw64(objsize);
2643 				efe->l_ad     = udf_rw32(l_ad);
2644 				efe->tag.desc_crc_len = udf_rw16(crclen);
2645 			}
2646 			/* eventually copy in evacuated piece */
2647 			/* set new size for uvm */
2648 			uvm_vnp_setsize(vp, new_size);
2649 
2650 			free(node_ad_cpy, M_UDFMNT);
2651 			udf_node_sanity_check(udf_node, &new_inflen, &new_lbrec);
2652 
2653 			UDF_UNLOCK_NODE(udf_node, 0);
2654 
2655 			KASSERT(new_inflen == orig_inflen - size_diff);
2656 			KASSERT(new_inflen == 0);
2657 			KASSERT(new_lbrec == 0);
2658 
2659 			return 0;
2660 		}
2661 
2662 		printf("UDF_SHRINK_NODE: could convert to internal alloc!\n");
2663 	}
2664 
2665 	/* 5) reset node descriptors */
2666 	udf_wipe_adslots(udf_node);
2667 
2668 	/* 6) copy back extents; merge when possible. Recounting on the fly */
2669 	cpy_slots = cpy_slot;
2670 
2671 	c_ad = node_ad_cpy[0];
2672 	slot = 0;
2673 	for (cpy_slot = 1; cpy_slot < cpy_slots; cpy_slot++) {
2674 		s_ad = node_ad_cpy[cpy_slot];
2675 
2676 		DPRINTF(ALLOC, ("\t6: stack -> got mapping vp %d "
2677 			"lb %d, len %d, flags %d\n",
2678 		udf_rw16(s_ad.loc.part_num),
2679 		udf_rw32(s_ad.loc.lb_num),
2680 		UDF_EXT_LEN(udf_rw32(s_ad.len)),
2681 		UDF_EXT_FLAGS(udf_rw32(s_ad.len)) >> 30));
2682 
2683 		/* see if we can merge */
2684 		if (udf_ads_merge(lb_size, &c_ad, &s_ad)) {
2685 			/* not mergable (anymore) */
2686 			DPRINTF(ALLOC, ("\t6: appending vp %d lb %d, "
2687 				"len %d, flags %d\n",
2688 			udf_rw16(c_ad.loc.part_num),
2689 			udf_rw32(c_ad.loc.lb_num),
2690 			UDF_EXT_LEN(udf_rw32(c_ad.len)),
2691 			UDF_EXT_FLAGS(udf_rw32(c_ad.len)) >> 30));
2692 
2693 			error = udf_append_adslot(udf_node, &slot, &c_ad);
2694 			if (error)
2695 				goto errorout; /* panic? */
2696 			c_ad = s_ad;
2697 			slot++;
2698 		}
2699 	}
2700 
2701 	/* 7) push rest slot (if any) */
2702 	if (UDF_EXT_LEN(c_ad.len) > 0) {
2703 		DPRINTF(ALLOC, ("\t7: last append vp %d lb %d, "
2704 				"len %d, flags %d\n",
2705 		udf_rw16(c_ad.loc.part_num),
2706 		udf_rw32(c_ad.loc.lb_num),
2707 		UDF_EXT_LEN(udf_rw32(c_ad.len)),
2708 		UDF_EXT_FLAGS(udf_rw32(c_ad.len)) >> 30));
2709 
2710 		error = udf_append_adslot(udf_node, &slot, &c_ad);
2711 		if (error)
2712 			goto errorout; /* panic? */
2713 		;
2714 	}
2715 
2716 	inflen  -= size_diff;
2717 	objsize -= size_diff;
2718 	if (fe) {
2719 		fe->inf_len   = udf_rw64(inflen);
2720 	} else {
2721 		efe->inf_len  = udf_rw64(inflen);
2722 		efe->obj_size = udf_rw64(objsize);
2723 	}
2724 	error = 0;
2725 
2726 	/* set new size for uvm */
2727 	uvm_vnp_setsize(vp, new_size);
2728 
2729 errorout:
2730 	free(node_ad_cpy, M_UDFMNT);
2731 
2732 	udf_count_alloc_exts(udf_node);
2733 
2734 	udf_node_sanity_check(udf_node, &new_inflen, &new_lbrec);
2735 	UDF_UNLOCK_NODE(udf_node, 0);
2736 
2737 	KASSERT(new_inflen == orig_inflen - size_diff);
2738 
2739 	return error;
2740 }
2741 
2742