xref: /freebsd/sys/fs/udf/udf_vnops.c (revision a2aef24aa3c8458e4036735dd6928b4ef77294e5)
1 /*-
2  * Copyright (c) 2001, 2002 Scott Long <scottl@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 /* udf_vnops.c */
30 /* Take care of the vnode side of things */
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/namei.h>
35 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/stat.h>
38 #include <sys/bio.h>
39 #include <sys/conf.h>
40 #include <sys/buf.h>
41 #include <sys/iconv.h>
42 #include <sys/mount.h>
43 #include <sys/vnode.h>
44 #include <sys/dirent.h>
45 #include <sys/queue.h>
46 #include <sys/unistd.h>
47 #include <sys/endian.h>
48 
49 #include <vm/uma.h>
50 
51 #include <fs/udf/ecma167-udf.h>
52 #include <fs/udf/osta.h>
53 #include <fs/udf/udf.h>
54 #include <fs/udf/udf_mount.h>
55 
56 extern struct iconv_functions *udf_iconv;
57 
58 static vop_access_t	udf_access;
59 static vop_getattr_t	udf_getattr;
60 static vop_open_t	udf_open;
61 static vop_ioctl_t	udf_ioctl;
62 static vop_pathconf_t	udf_pathconf;
63 static vop_print_t	udf_print;
64 static vop_read_t	udf_read;
65 static vop_readdir_t	udf_readdir;
66 static vop_readlink_t	udf_readlink;
67 static vop_setattr_t	udf_setattr;
68 static vop_strategy_t	udf_strategy;
69 static vop_bmap_t	udf_bmap;
70 static vop_cachedlookup_t	udf_lookup;
71 static vop_reclaim_t	udf_reclaim;
72 static vop_vptofh_t	udf_vptofh;
73 static int udf_readatoffset(struct udf_node *node, int *size, off_t offset,
74     struct buf **bp, uint8_t **data);
75 static int udf_bmap_internal(struct udf_node *node, off_t offset,
76     daddr_t *sector, uint32_t *max_size);
77 
78 static struct vop_vector udf_vnodeops = {
79 	.vop_default =		&default_vnodeops,
80 
81 	.vop_access =		udf_access,
82 	.vop_bmap =		udf_bmap,
83 	.vop_cachedlookup =	udf_lookup,
84 	.vop_getattr =		udf_getattr,
85 	.vop_ioctl =		udf_ioctl,
86 	.vop_lookup =		vfs_cache_lookup,
87 	.vop_open =		udf_open,
88 	.vop_pathconf =		udf_pathconf,
89 	.vop_print =		udf_print,
90 	.vop_read =		udf_read,
91 	.vop_readdir =		udf_readdir,
92 	.vop_readlink =		udf_readlink,
93 	.vop_reclaim =		udf_reclaim,
94 	.vop_setattr =		udf_setattr,
95 	.vop_strategy =		udf_strategy,
96 	.vop_vptofh =		udf_vptofh,
97 };
98 
99 struct vop_vector udf_fifoops = {
100 	.vop_default =		&fifo_specops,
101 	.vop_access =		udf_access,
102 	.vop_getattr =		udf_getattr,
103 	.vop_print =		udf_print,
104 	.vop_reclaim =		udf_reclaim,
105 	.vop_setattr =		udf_setattr,
106 	.vop_vptofh =		udf_vptofh,
107 };
108 
109 static MALLOC_DEFINE(M_UDFFID, "udf_fid", "UDF FileId structure");
110 static MALLOC_DEFINE(M_UDFDS, "udf_ds", "UDF Dirstream structure");
111 
112 #define UDF_INVALID_BMAP	-1
113 
114 int
115 udf_allocv(struct mount *mp, struct vnode **vpp, struct thread *td)
116 {
117 	int error;
118 	struct vnode *vp;
119 
120 	error = getnewvnode("udf", mp, &udf_vnodeops, &vp);
121 	if (error) {
122 		printf("udf_allocv: failed to allocate new vnode\n");
123 		return (error);
124 	}
125 
126 	*vpp = vp;
127 	return (0);
128 }
129 
130 /* Convert file entry permission (5 bits per owner/group/user) to a mode_t */
131 static mode_t
132 udf_permtomode(struct udf_node *node)
133 {
134 	uint32_t perm;
135 	uint16_t flags;
136 	mode_t mode;
137 
138 	perm = le32toh(node->fentry->perm);
139 	flags = le16toh(node->fentry->icbtag.flags);
140 
141 	mode = perm & UDF_FENTRY_PERM_USER_MASK;
142 	mode |= ((perm & UDF_FENTRY_PERM_GRP_MASK) >> 2);
143 	mode |= ((perm & UDF_FENTRY_PERM_OWNER_MASK) >> 4);
144 	mode |= ((flags & UDF_ICB_TAG_FLAGS_STICKY) << 4);
145 	mode |= ((flags & UDF_ICB_TAG_FLAGS_SETGID) << 6);
146 	mode |= ((flags & UDF_ICB_TAG_FLAGS_SETUID) << 8);
147 
148 	return (mode);
149 }
150 
151 static int
152 udf_access(struct vop_access_args *a)
153 {
154 	struct vnode *vp;
155 	struct udf_node *node;
156 	accmode_t accmode;
157 	mode_t mode;
158 
159 	vp = a->a_vp;
160 	node = VTON(vp);
161 	accmode = a->a_accmode;
162 
163 	if (accmode & VWRITE) {
164 		switch (vp->v_type) {
165 		case VDIR:
166 		case VLNK:
167 		case VREG:
168 			return (EROFS);
169 			/* NOT REACHED */
170 		default:
171 			break;
172 		}
173 	}
174 
175 	mode = udf_permtomode(node);
176 
177 	return (vaccess(vp->v_type, mode, node->fentry->uid, node->fentry->gid,
178 	    accmode, a->a_cred, NULL));
179 }
180 
181 static int
182 udf_open(struct vop_open_args *ap) {
183 	struct udf_node *np = VTON(ap->a_vp);
184 	off_t fsize;
185 
186 	fsize = le64toh(np->fentry->inf_len);
187 	vnode_create_vobject(ap->a_vp, fsize, ap->a_td);
188 	return 0;
189 }
190 
191 static const int mon_lens[2][12] = {
192 	{0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334},
193 	{0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335}
194 };
195 
196 static int
197 udf_isaleapyear(int year)
198 {
199 	int i;
200 
201 	i = (year % 4) ? 0 : 1;
202 	i &= (year % 100) ? 1 : 0;
203 	i |= (year % 400) ? 0 : 1;
204 
205 	return i;
206 }
207 
208 /*
209  * Timezone calculation compliments of Julian Elischer <julian@elischer.org>.
210  */
211 static void
212 udf_timetotimespec(struct timestamp *time, struct timespec *t)
213 {
214 	int i, lpyear, daysinyear, year, startyear;
215 	union {
216 		uint16_t	u_tz_offset;
217 		int16_t		s_tz_offset;
218 	} tz;
219 
220 	/*
221 	 * DirectCD seems to like using bogus year values.
222 	 * Don't trust time->month as it will be used for an array index.
223 	 */
224 	year = le16toh(time->year);
225 	if (year < 1970 || time->month < 1 || time->month > 12) {
226 		t->tv_sec = 0;
227 		t->tv_nsec = 0;
228 		return;
229 	}
230 
231 	/* Calculate the time and day */
232 	t->tv_sec = time->second;
233 	t->tv_sec += time->minute * 60;
234 	t->tv_sec += time->hour * 3600;
235 	t->tv_sec += (time->day - 1) * 3600 * 24;
236 
237 	/* Calculate the month */
238 	lpyear = udf_isaleapyear(year);
239 	t->tv_sec += mon_lens[lpyear][time->month - 1] * 3600 * 24;
240 
241 	/* Speed up the calculation */
242 	startyear = 1970;
243 	if (year > 2009) {
244 		t->tv_sec += 1262304000;
245 		startyear += 40;
246 	} else if (year > 1999) {
247 		t->tv_sec += 946684800;
248 		startyear += 30;
249 	} else if (year > 1989) {
250 		t->tv_sec += 631152000;
251 		startyear += 20;
252 	} else if (year > 1979) {
253 		t->tv_sec += 315532800;
254 		startyear += 10;
255 	}
256 
257 	daysinyear = (year - startyear) * 365;
258 	for (i = startyear; i < year; i++)
259 		daysinyear += udf_isaleapyear(i);
260 	t->tv_sec += daysinyear * 3600 * 24;
261 
262 	/* Calculate microseconds */
263 	t->tv_nsec = time->centisec * 10000 + time->hund_usec * 100 +
264 	    time->usec;
265 
266 	/*
267 	 * Calculate the time zone.  The timezone is 12 bit signed 2's
268 	 * complement, so we gotta do some extra magic to handle it right.
269 	 */
270 	tz.u_tz_offset = le16toh(time->type_tz);
271 	tz.u_tz_offset &= 0x0fff;
272 	if (tz.u_tz_offset & 0x0800)
273 		tz.u_tz_offset |= 0xf000;	/* extend the sign to 16 bits */
274 	if ((le16toh(time->type_tz) & 0x1000) && (tz.s_tz_offset != -2047))
275 		t->tv_sec -= tz.s_tz_offset * 60;
276 
277 	return;
278 }
279 
280 static int
281 udf_getattr(struct vop_getattr_args *a)
282 {
283 	struct vnode *vp;
284 	struct udf_node *node;
285 	struct vattr *vap;
286 	struct file_entry *fentry;
287 	struct timespec ts;
288 
289 	ts.tv_sec = 0;
290 
291 	vp = a->a_vp;
292 	vap = a->a_vap;
293 	node = VTON(vp);
294 	fentry = node->fentry;
295 
296 	vap->va_fsid = dev2udev(node->udfmp->im_dev);
297 	vap->va_fileid = node->hash_id;
298 	vap->va_mode = udf_permtomode(node);
299 	vap->va_nlink = le16toh(fentry->link_cnt);
300 	/*
301 	 * XXX The spec says that -1 is valid for uid/gid and indicates an
302 	 * invalid uid/gid.  How should this be represented?
303 	 */
304 	vap->va_uid = (le32toh(fentry->uid) == -1) ? 0 : le32toh(fentry->uid);
305 	vap->va_gid = (le32toh(fentry->gid) == -1) ? 0 : le32toh(fentry->gid);
306 	udf_timetotimespec(&fentry->atime, &vap->va_atime);
307 	udf_timetotimespec(&fentry->mtime, &vap->va_mtime);
308 	vap->va_ctime = vap->va_mtime; /* XXX Stored as an Extended Attribute */
309 	vap->va_rdev = NODEV;
310 	if (vp->v_type & VDIR) {
311 		/*
312 		 * Directories that are recorded within their ICB will show
313 		 * as having 0 blocks recorded.  Since tradition dictates
314 		 * that directories consume at least one logical block,
315 		 * make it appear so.
316 		 */
317 		if (fentry->logblks_rec != 0) {
318 			vap->va_size =
319 			    le64toh(fentry->logblks_rec) * node->udfmp->bsize;
320 		} else {
321 			vap->va_size = node->udfmp->bsize;
322 		}
323 	} else {
324 		vap->va_size = le64toh(fentry->inf_len);
325 	}
326 	vap->va_flags = 0;
327 	vap->va_gen = 1;
328 	vap->va_blocksize = node->udfmp->bsize;
329 	vap->va_bytes = le64toh(fentry->inf_len);
330 	vap->va_type = vp->v_type;
331 	vap->va_filerev = 0; /* XXX */
332 	return (0);
333 }
334 
335 static int
336 udf_setattr(struct vop_setattr_args *a)
337 {
338 	struct vnode *vp;
339 	struct vattr *vap;
340 
341 	vp = a->a_vp;
342 	vap = a->a_vap;
343 	if (vap->va_flags != (u_long)VNOVAL || vap->va_uid != (uid_t)VNOVAL ||
344 	    vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL ||
345 	    vap->va_mtime.tv_sec != VNOVAL || vap->va_mode != (mode_t)VNOVAL)
346 		return (EROFS);
347 	if (vap->va_size != (u_quad_t)VNOVAL) {
348 		switch (vp->v_type) {
349 		case VDIR:
350 			return (EISDIR);
351 		case VLNK:
352 		case VREG:
353 			return (EROFS);
354 		case VCHR:
355 		case VBLK:
356 		case VSOCK:
357 		case VFIFO:
358 		case VNON:
359 		case VBAD:
360 		case VMARKER:
361 			return (0);
362 		}
363 	}
364 	return (0);
365 }
366 
367 /*
368  * File specific ioctls.
369  */
370 static int
371 udf_ioctl(struct vop_ioctl_args *a)
372 {
373 	printf("%s called\n", __func__);
374 	return (ENOTTY);
375 }
376 
377 /*
378  * I'm not sure that this has much value in a read-only filesystem, but
379  * cd9660 has it too.
380  */
381 static int
382 udf_pathconf(struct vop_pathconf_args *a)
383 {
384 
385 	switch (a->a_name) {
386 	case _PC_FILESIZEBITS:
387 		*a->a_retval = 64;
388 		return (0);
389 	case _PC_LINK_MAX:
390 		*a->a_retval = 65535;
391 		return (0);
392 	case _PC_NAME_MAX:
393 		*a->a_retval = NAME_MAX;
394 		return (0);
395 	case _PC_SYMLINK_MAX:
396 		*a->a_retval = MAXPATHLEN;
397 		return (0);
398 	case _PC_NO_TRUNC:
399 		*a->a_retval = 1;
400 		return (0);
401 	default:
402 		return (vop_stdpathconf(a));
403 	}
404 }
405 
406 static int
407 udf_print(struct vop_print_args *ap)
408 {
409 	struct vnode *vp = ap->a_vp;
410 	struct udf_node *node = VTON(vp);
411 
412 	printf("    ino %lu, on dev %s", (u_long)node->hash_id,
413 	    devtoname(node->udfmp->im_dev));
414 	if (vp->v_type == VFIFO)
415 		fifo_printinfo(vp);
416 	printf("\n");
417 	return (0);
418 }
419 
420 #define lblkno(udfmp, loc)	((loc) >> (udfmp)->bshift)
421 #define blkoff(udfmp, loc)	((loc) & (udfmp)->bmask)
422 #define lblktosize(udfmp, blk)	((blk) << (udfmp)->bshift)
423 
424 static inline int
425 is_data_in_fentry(const struct udf_node *node)
426 {
427 	const struct file_entry *fentry = node->fentry;
428 
429 	return ((le16toh(fentry->icbtag.flags) & 0x7) == 3);
430 }
431 
432 static int
433 udf_read(struct vop_read_args *ap)
434 {
435 	struct vnode *vp = ap->a_vp;
436 	struct uio *uio = ap->a_uio;
437 	struct udf_node *node = VTON(vp);
438 	struct udf_mnt *udfmp;
439 	struct file_entry *fentry;
440 	struct buf *bp;
441 	uint8_t *data;
442 	daddr_t lbn, rablock;
443 	off_t diff, fsize;
444 	ssize_t n;
445 	int error = 0;
446 	long size, on;
447 
448 	if (uio->uio_resid == 0)
449 		return (0);
450 	if (uio->uio_offset < 0)
451 		return (EINVAL);
452 
453 	if (is_data_in_fentry(node)) {
454 		fentry = node->fentry;
455 		data = &fentry->data[le32toh(fentry->l_ea)];
456 		fsize = le32toh(fentry->l_ad);
457 
458 		n = uio->uio_resid;
459 		diff = fsize - uio->uio_offset;
460 		if (diff <= 0)
461 			return (0);
462 		if (diff < n)
463 			n = diff;
464 		error = uiomove(data + uio->uio_offset, (int)n, uio);
465 		return (error);
466 	}
467 
468 	fsize = le64toh(node->fentry->inf_len);
469 	udfmp = node->udfmp;
470 	do {
471 		lbn = lblkno(udfmp, uio->uio_offset);
472 		on = blkoff(udfmp, uio->uio_offset);
473 		n = min((u_int)(udfmp->bsize - on),
474 			uio->uio_resid);
475 		diff = fsize - uio->uio_offset;
476 		if (diff <= 0)
477 			return (0);
478 		if (diff < n)
479 			n = diff;
480 		size = udfmp->bsize;
481 		rablock = lbn + 1;
482 		if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
483 			if (lblktosize(udfmp, rablock) < fsize) {
484 				error = cluster_read(vp, fsize, lbn, size,
485 				    NOCRED, uio->uio_resid,
486 				    (ap->a_ioflag >> 16), 0, &bp);
487 			} else {
488 				error = bread(vp, lbn, size, NOCRED, &bp);
489 			}
490 		} else {
491 			error = bread(vp, lbn, size, NOCRED, &bp);
492 		}
493 		if (error != 0) {
494 			brelse(bp);
495 			return (error);
496 		}
497 		n = min(n, size - bp->b_resid);
498 
499 		error = uiomove(bp->b_data + on, (int)n, uio);
500 		brelse(bp);
501 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
502 	return (error);
503 }
504 
505 /*
506  * Call the OSTA routines to translate the name from a CS0 dstring to a
507  * 16-bit Unicode String.  Hooks need to be placed in here to translate from
508  * Unicode to the encoding that the kernel/user expects.  Return the length
509  * of the translated string.
510  */
511 static int
512 udf_transname(char *cs0string, char *destname, int len, struct udf_mnt *udfmp)
513 {
514 	unicode_t *transname;
515 	char *unibuf, *unip;
516 	int i, destlen;
517 	ssize_t unilen = 0;
518 	size_t destleft = MAXNAMLEN;
519 
520 	/* Convert 16-bit Unicode to destname */
521 	if (udfmp->im_flags & UDFMNT_KICONV && udf_iconv) {
522 		/* allocate a buffer big enough to hold an 8->16 bit expansion */
523 		unibuf = uma_zalloc(udf_zone_trans, M_WAITOK);
524 		unip = unibuf;
525 		if ((unilen = (ssize_t)udf_UncompressUnicodeByte(len, cs0string, unibuf)) == -1) {
526 			printf("udf: Unicode translation failed\n");
527 			uma_zfree(udf_zone_trans, unibuf);
528 			return 0;
529 		}
530 
531 		while (unilen > 0 && destleft > 0) {
532 			udf_iconv->conv(udfmp->im_d2l, __DECONST(const char **,
533 			    &unibuf), (size_t *)&unilen, (char **)&destname,
534 			    &destleft);
535 			/* Unconverted character found */
536 			if (unilen > 0 && destleft > 0) {
537 				*destname++ = '?';
538 				destleft--;
539 				unibuf += 2;
540 				unilen -= 2;
541 			}
542 		}
543 		uma_zfree(udf_zone_trans, unip);
544 		*destname = '\0';
545 		destlen = MAXNAMLEN - (int)destleft;
546 	} else {
547 		/* allocate a buffer big enough to hold an 8->16 bit expansion */
548 		transname = uma_zalloc(udf_zone_trans, M_WAITOK);
549 
550 		if ((unilen = (ssize_t)udf_UncompressUnicode(len, cs0string, transname)) == -1) {
551 			printf("udf: Unicode translation failed\n");
552 			uma_zfree(udf_zone_trans, transname);
553 			return 0;
554 		}
555 
556 		for (i = 0; i < unilen ; i++) {
557 			if (transname[i] & 0xff00) {
558 				destname[i] = '.';	/* Fudge the 16bit chars */
559 			} else {
560 				destname[i] = transname[i] & 0xff;
561 			}
562 		}
563 		uma_zfree(udf_zone_trans, transname);
564 		destname[unilen] = 0;
565 		destlen = (int)unilen;
566 	}
567 
568 	return (destlen);
569 }
570 
571 /*
572  * Compare a CS0 dstring with a name passed in from the VFS layer.  Return
573  * 0 on a successful match, nonzero otherwise.  Unicode work may need to be done
574  * here also.
575  */
576 static int
577 udf_cmpname(char *cs0string, char *cmpname, int cs0len, int cmplen, struct udf_mnt *udfmp)
578 {
579 	char *transname;
580 	int error = 0;
581 
582 	/* This is overkill, but not worth creating a new zone */
583 	transname = uma_zalloc(udf_zone_trans, M_WAITOK);
584 
585 	cs0len = udf_transname(cs0string, transname, cs0len, udfmp);
586 
587 	/* Easy check.  If they aren't the same length, they aren't equal */
588 	if ((cs0len == 0) || (cs0len != cmplen))
589 		error = -1;
590 	else
591 		error = bcmp(transname, cmpname, cmplen);
592 
593 	uma_zfree(udf_zone_trans, transname);
594 	return (error);
595 }
596 
597 struct udf_uiodir {
598 	struct dirent *dirent;
599 	u_long *cookies;
600 	int ncookies;
601 	int acookies;
602 	int eofflag;
603 };
604 
605 static int
606 udf_uiodir(struct udf_uiodir *uiodir, int de_size, struct uio *uio, long cookie)
607 {
608 	if (uiodir->cookies != NULL) {
609 		if (++uiodir->acookies > uiodir->ncookies) {
610 			uiodir->eofflag = 0;
611 			return (-1);
612 		}
613 		*uiodir->cookies++ = cookie;
614 	}
615 
616 	if (uio->uio_resid < de_size) {
617 		uiodir->eofflag = 0;
618 		return (-1);
619 	}
620 
621 	return (uiomove(uiodir->dirent, de_size, uio));
622 }
623 
624 static struct udf_dirstream *
625 udf_opendir(struct udf_node *node, int offset, int fsize, struct udf_mnt *udfmp)
626 {
627 	struct udf_dirstream *ds;
628 
629 	ds = uma_zalloc(udf_zone_ds, M_WAITOK | M_ZERO);
630 
631 	ds->node = node;
632 	ds->offset = offset;
633 	ds->udfmp = udfmp;
634 	ds->fsize = fsize;
635 
636 	return (ds);
637 }
638 
639 static struct fileid_desc *
640 udf_getfid(struct udf_dirstream *ds)
641 {
642 	struct fileid_desc *fid;
643 	int error, frag_size = 0, total_fid_size;
644 
645 	/* End of directory? */
646 	if (ds->offset + ds->off >= ds->fsize) {
647 		ds->error = 0;
648 		return (NULL);
649 	}
650 
651 	/* Grab the first extent of the directory */
652 	if (ds->off == 0) {
653 		ds->size = 0;
654 		error = udf_readatoffset(ds->node, &ds->size, ds->offset,
655 		    &ds->bp, &ds->data);
656 		if (error) {
657 			ds->error = error;
658 			if (ds->bp != NULL)
659 				brelse(ds->bp);
660 			return (NULL);
661 		}
662 	}
663 
664 	/*
665 	 * Clean up from a previous fragmented FID.
666 	 * XXX Is this the right place for this?
667 	 */
668 	if (ds->fid_fragment && ds->buf != NULL) {
669 		ds->fid_fragment = 0;
670 		free(ds->buf, M_UDFFID);
671 	}
672 
673 	fid = (struct fileid_desc*)&ds->data[ds->off];
674 
675 	/*
676 	 * Check to see if the fid is fragmented. The first test
677 	 * ensures that we don't wander off the end of the buffer
678 	 * looking for the l_iu and l_fi fields.
679 	 */
680 	if (ds->off + UDF_FID_SIZE > ds->size ||
681 	    ds->off + le16toh(fid->l_iu) + fid->l_fi + UDF_FID_SIZE > ds->size){
682 
683 		/* Copy what we have of the fid into a buffer */
684 		frag_size = ds->size - ds->off;
685 		if (frag_size >= ds->udfmp->bsize) {
686 			printf("udf: invalid FID fragment\n");
687 			ds->error = EINVAL;
688 			return (NULL);
689 		}
690 
691 		/*
692 		 * File ID descriptors can only be at most one
693 		 * logical sector in size.
694 		 */
695 		ds->buf = malloc(ds->udfmp->bsize, M_UDFFID,
696 		     M_WAITOK | M_ZERO);
697 		bcopy(fid, ds->buf, frag_size);
698 
699 		/* Reduce all of the casting magic */
700 		fid = (struct fileid_desc*)ds->buf;
701 
702 		if (ds->bp != NULL)
703 			brelse(ds->bp);
704 
705 		/* Fetch the next allocation */
706 		ds->offset += ds->size;
707 		ds->size = 0;
708 		error = udf_readatoffset(ds->node, &ds->size, ds->offset,
709 		    &ds->bp, &ds->data);
710 		if (error) {
711 			ds->error = error;
712 			return (NULL);
713 		}
714 
715 		/*
716 		 * If the fragment was so small that we didn't get
717 		 * the l_iu and l_fi fields, copy those in.
718 		 */
719 		if (frag_size < UDF_FID_SIZE)
720 			bcopy(ds->data, &ds->buf[frag_size],
721 			    UDF_FID_SIZE - frag_size);
722 
723 		/*
724 		 * Now that we have enough of the fid to work with,
725 		 * copy in the rest of the fid from the new
726 		 * allocation.
727 		 */
728 		total_fid_size = UDF_FID_SIZE + le16toh(fid->l_iu) + fid->l_fi;
729 		if (total_fid_size > ds->udfmp->bsize) {
730 			printf("udf: invalid FID\n");
731 			ds->error = EIO;
732 			return (NULL);
733 		}
734 		bcopy(ds->data, &ds->buf[frag_size],
735 		    total_fid_size - frag_size);
736 
737 		ds->fid_fragment = 1;
738 	} else {
739 		total_fid_size = le16toh(fid->l_iu) + fid->l_fi + UDF_FID_SIZE;
740 	}
741 
742 	/*
743 	 * Update the offset. Align on a 4 byte boundary because the
744 	 * UDF spec says so.
745 	 */
746 	ds->this_off = ds->offset + ds->off;
747 	if (!ds->fid_fragment) {
748 		ds->off += (total_fid_size + 3) & ~0x03;
749 	} else {
750 		ds->off = (total_fid_size - frag_size + 3) & ~0x03;
751 	}
752 
753 	return (fid);
754 }
755 
756 static void
757 udf_closedir(struct udf_dirstream *ds)
758 {
759 
760 	if (ds->bp != NULL)
761 		brelse(ds->bp);
762 
763 	if (ds->fid_fragment && ds->buf != NULL)
764 		free(ds->buf, M_UDFFID);
765 
766 	uma_zfree(udf_zone_ds, ds);
767 }
768 
769 static int
770 udf_readdir(struct vop_readdir_args *a)
771 {
772 	struct vnode *vp;
773 	struct uio *uio;
774 	struct dirent dir;
775 	struct udf_node *node;
776 	struct udf_mnt *udfmp;
777 	struct fileid_desc *fid;
778 	struct udf_uiodir uiodir;
779 	struct udf_dirstream *ds;
780 	u_long *cookies = NULL;
781 	int ncookies;
782 	int error = 0;
783 
784 	vp = a->a_vp;
785 	uio = a->a_uio;
786 	node = VTON(vp);
787 	udfmp = node->udfmp;
788 	uiodir.eofflag = 1;
789 
790 	if (a->a_ncookies != NULL) {
791 		/*
792 		 * Guess how many entries are needed.  If we run out, this
793 		 * function will be called again and thing will pick up were
794 		 * it left off.
795 		 */
796 		ncookies = uio->uio_resid / 8;
797 		cookies = malloc(sizeof(u_long) * ncookies,
798 		    M_TEMP, M_WAITOK);
799 		if (cookies == NULL)
800 			return (ENOMEM);
801 		uiodir.ncookies = ncookies;
802 		uiodir.cookies = cookies;
803 		uiodir.acookies = 0;
804 	} else {
805 		uiodir.cookies = NULL;
806 	}
807 
808 	/*
809 	 * Iterate through the file id descriptors.  Give the parent dir
810 	 * entry special attention.
811 	 */
812 	ds = udf_opendir(node, uio->uio_offset, le64toh(node->fentry->inf_len),
813 	    node->udfmp);
814 
815 	while ((fid = udf_getfid(ds)) != NULL) {
816 
817 		/* XXX Should we return an error on a bad fid? */
818 		if (udf_checktag(&fid->tag, TAGID_FID)) {
819 			printf("Invalid FID tag\n");
820 			hexdump(fid, UDF_FID_SIZE, NULL, 0);
821 			error = EIO;
822 			break;
823 		}
824 
825 		/* Is this a deleted file? */
826 		if (fid->file_char & UDF_FILE_CHAR_DEL)
827 			continue;
828 
829 		if ((fid->l_fi == 0) && (fid->file_char & UDF_FILE_CHAR_PAR)) {
830 			/* Do up the '.' and '..' entries.  Dummy values are
831 			 * used for the cookies since the offset here is
832 			 * usually zero, and NFS doesn't like that value
833 			 */
834 			dir.d_fileno = node->hash_id;
835 			dir.d_type = DT_DIR;
836 			dir.d_name[0] = '.';
837 			dir.d_name[1] = '\0';
838 			dir.d_namlen = 1;
839 			dir.d_reclen = GENERIC_DIRSIZ(&dir);
840 			uiodir.dirent = &dir;
841 			error = udf_uiodir(&uiodir, dir.d_reclen, uio, 1);
842 			if (error)
843 				break;
844 
845 			dir.d_fileno = udf_getid(&fid->icb);
846 			dir.d_type = DT_DIR;
847 			dir.d_name[0] = '.';
848 			dir.d_name[1] = '.';
849 			dir.d_name[2] = '\0';
850 			dir.d_namlen = 2;
851 			dir.d_reclen = GENERIC_DIRSIZ(&dir);
852 			uiodir.dirent = &dir;
853 			error = udf_uiodir(&uiodir, dir.d_reclen, uio, 2);
854 		} else {
855 			dir.d_namlen = udf_transname(&fid->data[fid->l_iu],
856 			    &dir.d_name[0], fid->l_fi, udfmp);
857 			dir.d_fileno = udf_getid(&fid->icb);
858 			dir.d_type = (fid->file_char & UDF_FILE_CHAR_DIR) ?
859 			    DT_DIR : DT_UNKNOWN;
860 			dir.d_reclen = GENERIC_DIRSIZ(&dir);
861 			uiodir.dirent = &dir;
862 			error = udf_uiodir(&uiodir, dir.d_reclen, uio,
863 			    ds->this_off);
864 		}
865 		if (error)
866 			break;
867 		uio->uio_offset = ds->offset + ds->off;
868 	}
869 
870 	/* tell the calling layer whether we need to be called again */
871 	*a->a_eofflag = uiodir.eofflag;
872 
873 	if (error < 0)
874 		error = 0;
875 	if (!error)
876 		error = ds->error;
877 
878 	udf_closedir(ds);
879 
880 	if (a->a_ncookies != NULL) {
881 		if (error)
882 			free(cookies, M_TEMP);
883 		else {
884 			*a->a_ncookies = uiodir.acookies;
885 			*a->a_cookies = cookies;
886 		}
887 	}
888 
889 	return (error);
890 }
891 
892 static int
893 udf_readlink(struct vop_readlink_args *ap)
894 {
895 	struct path_component *pc, *end;
896 	struct vnode *vp;
897 	struct uio uio;
898 	struct iovec iov[1];
899 	struct udf_node *node;
900 	void *buf;
901 	char *cp;
902 	int error, len, root;
903 
904 	/*
905 	 * A symbolic link in UDF is a list of variable-length path
906 	 * component structures.  We build a pathname in the caller's
907 	 * uio by traversing this list.
908 	 */
909 	vp = ap->a_vp;
910 	node = VTON(vp);
911 	len = le64toh(node->fentry->inf_len);
912 	buf = malloc(len, M_DEVBUF, M_WAITOK);
913 	iov[0].iov_len = len;
914 	iov[0].iov_base = buf;
915 	uio.uio_iov = iov;
916 	uio.uio_iovcnt = 1;
917 	uio.uio_offset = 0;
918 	uio.uio_resid = iov[0].iov_len;
919 	uio.uio_segflg = UIO_SYSSPACE;
920 	uio.uio_rw = UIO_READ;
921 	uio.uio_td = curthread;
922 	error = VOP_READ(vp, &uio, 0, ap->a_cred);
923 	if (error)
924 		goto error;
925 
926 	pc = buf;
927 	end = (void *)((char *)buf + len);
928 	root = 0;
929 	while (pc < end) {
930 		switch (pc->type) {
931 		case UDF_PATH_ROOT:
932 			/* Only allow this at the beginning of a path. */
933 			if ((void *)pc != buf) {
934 				error = EINVAL;
935 				goto error;
936 			}
937 			cp = "/";
938 			len = 1;
939 			root = 1;
940 			break;
941 		case UDF_PATH_DOT:
942 			cp = ".";
943 			len = 1;
944 			break;
945 		case UDF_PATH_DOTDOT:
946 			cp = "..";
947 			len = 2;
948 			break;
949 		case UDF_PATH_PATH:
950 			if (pc->length == 0) {
951 				error = EINVAL;
952 				goto error;
953 			}
954 			/*
955 			 * XXX: We only support CS8 which appears to map
956 			 * to ASCII directly.
957 			 */
958 			switch (pc->identifier[0]) {
959 			case 8:
960 				cp = pc->identifier + 1;
961 				len = pc->length - 1;
962 				break;
963 			default:
964 				error = EOPNOTSUPP;
965 				goto error;
966 			}
967 			break;
968 		default:
969 			error = EINVAL;
970 			goto error;
971 		}
972 
973 		/*
974 		 * If this is not the first component, insert a path
975 		 * separator.
976 		 */
977 		if (pc != buf) {
978 			/* If we started with root we already have a "/". */
979 			if (root)
980 				goto skipslash;
981 			root = 0;
982 			if (ap->a_uio->uio_resid < 1) {
983 				error = ENAMETOOLONG;
984 				goto error;
985 			}
986 			error = uiomove("/", 1, ap->a_uio);
987 			if (error)
988 				break;
989 		}
990 	skipslash:
991 
992 		/* Append string at 'cp' of length 'len' to our path. */
993 		if (len > ap->a_uio->uio_resid) {
994 			error = ENAMETOOLONG;
995 			goto error;
996 		}
997 		error = uiomove(cp, len, ap->a_uio);
998 		if (error)
999 			break;
1000 
1001 		/* Advance to next component. */
1002 		pc = (void *)((char *)pc + 4 + pc->length);
1003 	}
1004 error:
1005 	free(buf, M_DEVBUF);
1006 	return (error);
1007 }
1008 
1009 static int
1010 udf_strategy(struct vop_strategy_args *a)
1011 {
1012 	struct buf *bp;
1013 	struct vnode *vp;
1014 	struct udf_node *node;
1015 	struct bufobj *bo;
1016 	off_t offset;
1017 	uint32_t maxsize;
1018 	daddr_t sector;
1019 	int error;
1020 
1021 	bp = a->a_bp;
1022 	vp = a->a_vp;
1023 	node = VTON(vp);
1024 
1025 	if (bp->b_blkno == bp->b_lblkno) {
1026 		offset = lblktosize(node->udfmp, bp->b_lblkno);
1027 		error = udf_bmap_internal(node, offset, &sector, &maxsize);
1028 		if (error) {
1029 			clrbuf(bp);
1030 			bp->b_blkno = -1;
1031 			bufdone(bp);
1032 			return (0);
1033 		}
1034 		/* bmap gives sector numbers, bio works with device blocks */
1035 		bp->b_blkno = sector << (node->udfmp->bshift - DEV_BSHIFT);
1036 	}
1037 	bo = node->udfmp->im_bo;
1038 	bp->b_iooffset = dbtob(bp->b_blkno);
1039 	BO_STRATEGY(bo, bp);
1040 	return (0);
1041 }
1042 
1043 static int
1044 udf_bmap(struct vop_bmap_args *a)
1045 {
1046 	struct udf_node *node;
1047 	uint32_t max_size;
1048 	daddr_t lsector;
1049 	int nblk;
1050 	int error;
1051 
1052 	node = VTON(a->a_vp);
1053 
1054 	if (a->a_bop != NULL)
1055 		*a->a_bop = &node->udfmp->im_devvp->v_bufobj;
1056 	if (a->a_bnp == NULL)
1057 		return (0);
1058 	if (a->a_runb)
1059 		*a->a_runb = 0;
1060 
1061 	/*
1062 	 * UDF_INVALID_BMAP means data embedded into fentry, this is an internal
1063 	 * error that should not be propagated to calling code.
1064 	 * Most obvious mapping for this error is EOPNOTSUPP as we can not truly
1065 	 * translate block numbers in this case.
1066 	 * Incidentally, this return code will make vnode pager to use VOP_READ
1067 	 * to get data for mmap-ed pages and udf_read knows how to do the right
1068 	 * thing for this kind of files.
1069 	 */
1070 	error = udf_bmap_internal(node, a->a_bn << node->udfmp->bshift,
1071 	    &lsector, &max_size);
1072 	if (error == UDF_INVALID_BMAP)
1073 		return (EOPNOTSUPP);
1074 	if (error)
1075 		return (error);
1076 
1077 	/* Translate logical to physical sector number */
1078 	*a->a_bnp = lsector << (node->udfmp->bshift - DEV_BSHIFT);
1079 
1080 	/*
1081 	 * Determine maximum number of readahead blocks following the
1082 	 * requested block.
1083 	 */
1084 	if (a->a_runp) {
1085 		nblk = (max_size >> node->udfmp->bshift) - 1;
1086 		if (nblk <= 0)
1087 			*a->a_runp = 0;
1088 		else if (nblk >= (MAXBSIZE >> node->udfmp->bshift))
1089 			*a->a_runp = (MAXBSIZE >> node->udfmp->bshift) - 1;
1090 		else
1091 			*a->a_runp = nblk;
1092 	}
1093 
1094 	if (a->a_runb) {
1095 		*a->a_runb = 0;
1096 	}
1097 
1098 	return (0);
1099 }
1100 
1101 /*
1102  * The all powerful VOP_LOOKUP().
1103  */
1104 static int
1105 udf_lookup(struct vop_cachedlookup_args *a)
1106 {
1107 	struct vnode *dvp;
1108 	struct vnode *tdp = NULL;
1109 	struct vnode **vpp = a->a_vpp;
1110 	struct udf_node *node;
1111 	struct udf_mnt *udfmp;
1112 	struct fileid_desc *fid = NULL;
1113 	struct udf_dirstream *ds;
1114 	u_long nameiop;
1115 	u_long flags;
1116 	char *nameptr;
1117 	long namelen;
1118 	ino_t id = 0;
1119 	int offset, error = 0;
1120 	int fsize, lkflags, ltype, numdirpasses;
1121 
1122 	dvp = a->a_dvp;
1123 	node = VTON(dvp);
1124 	udfmp = node->udfmp;
1125 	nameiop = a->a_cnp->cn_nameiop;
1126 	flags = a->a_cnp->cn_flags;
1127 	lkflags = a->a_cnp->cn_lkflags;
1128 	nameptr = a->a_cnp->cn_nameptr;
1129 	namelen = a->a_cnp->cn_namelen;
1130 	fsize = le64toh(node->fentry->inf_len);
1131 
1132 	/*
1133 	 * If this is a LOOKUP and we've already partially searched through
1134 	 * the directory, pick up where we left off and flag that the
1135 	 * directory may need to be searched twice.  For a full description,
1136 	 * see /sys/fs/cd9660/cd9660_lookup.c:cd9660_lookup()
1137 	 */
1138 	if (nameiop != LOOKUP || node->diroff == 0 || node->diroff > fsize) {
1139 		offset = 0;
1140 		numdirpasses = 1;
1141 	} else {
1142 		offset = node->diroff;
1143 		numdirpasses = 2;
1144 		nchstats.ncs_2passes++;
1145 	}
1146 
1147 lookloop:
1148 	ds = udf_opendir(node, offset, fsize, udfmp);
1149 
1150 	while ((fid = udf_getfid(ds)) != NULL) {
1151 
1152 		/* XXX Should we return an error on a bad fid? */
1153 		if (udf_checktag(&fid->tag, TAGID_FID)) {
1154 			printf("udf_lookup: Invalid tag\n");
1155 			error = EIO;
1156 			break;
1157 		}
1158 
1159 		/* Is this a deleted file? */
1160 		if (fid->file_char & UDF_FILE_CHAR_DEL)
1161 			continue;
1162 
1163 		if ((fid->l_fi == 0) && (fid->file_char & UDF_FILE_CHAR_PAR)) {
1164 			if (flags & ISDOTDOT) {
1165 				id = udf_getid(&fid->icb);
1166 				break;
1167 			}
1168 		} else {
1169 			if (!(udf_cmpname(&fid->data[fid->l_iu],
1170 			    nameptr, fid->l_fi, namelen, udfmp))) {
1171 				id = udf_getid(&fid->icb);
1172 				break;
1173 			}
1174 		}
1175 	}
1176 
1177 	if (!error)
1178 		error = ds->error;
1179 
1180 	/* XXX Bail out here? */
1181 	if (error) {
1182 		udf_closedir(ds);
1183 		return (error);
1184 	}
1185 
1186 	/* Did we have a match? */
1187 	if (id) {
1188 		/*
1189 		 * Remember where this entry was if it's the final
1190 		 * component.
1191 		 */
1192 		if ((flags & ISLASTCN) && nameiop == LOOKUP)
1193 			node->diroff = ds->offset + ds->off;
1194 		if (numdirpasses == 2)
1195 			nchstats.ncs_pass2++;
1196 		udf_closedir(ds);
1197 
1198 		if (flags & ISDOTDOT) {
1199 			error = vn_vget_ino(dvp, id, lkflags, &tdp);
1200 		} else if (node->hash_id == id) {
1201 			VREF(dvp);	/* we want ourself, ie "." */
1202 			/*
1203 			 * When we lookup "." we still can be asked to lock it
1204 			 * differently.
1205 			 */
1206 			ltype = lkflags & LK_TYPE_MASK;
1207 			if (ltype != VOP_ISLOCKED(dvp)) {
1208 				if (ltype == LK_EXCLUSIVE)
1209 					vn_lock(dvp, LK_UPGRADE | LK_RETRY);
1210 				else /* if (ltype == LK_SHARED) */
1211 					vn_lock(dvp, LK_DOWNGRADE | LK_RETRY);
1212 			}
1213 			tdp = dvp;
1214 		} else
1215 			error = udf_vget(udfmp->im_mountp, id, lkflags, &tdp);
1216 		if (!error) {
1217 			*vpp = tdp;
1218 			/* Put this entry in the cache */
1219 			if (flags & MAKEENTRY)
1220 				cache_enter(dvp, *vpp, a->a_cnp);
1221 		}
1222 	} else {
1223 		/* Name wasn't found on this pass.  Do another pass? */
1224 		if (numdirpasses == 2) {
1225 			numdirpasses--;
1226 			offset = 0;
1227 			udf_closedir(ds);
1228 			goto lookloop;
1229 		}
1230 		udf_closedir(ds);
1231 
1232 		/* Enter name into cache as non-existant */
1233 		if (flags & MAKEENTRY)
1234 			cache_enter(dvp, *vpp, a->a_cnp);
1235 
1236 		if ((flags & ISLASTCN) &&
1237 		    (nameiop == CREATE || nameiop == RENAME)) {
1238 			error = EROFS;
1239 		} else {
1240 			error = ENOENT;
1241 		}
1242 	}
1243 
1244 	return (error);
1245 }
1246 
1247 static int
1248 udf_reclaim(struct vop_reclaim_args *a)
1249 {
1250 	struct vnode *vp;
1251 	struct udf_node *unode;
1252 
1253 	vp = a->a_vp;
1254 	unode = VTON(vp);
1255 
1256 	/*
1257 	 * Destroy the vm object and flush associated pages.
1258 	 */
1259 	vnode_destroy_vobject(vp);
1260 
1261 	if (unode != NULL) {
1262 		vfs_hash_remove(vp);
1263 
1264 		if (unode->fentry != NULL)
1265 			free(unode->fentry, M_UDFFENTRY);
1266 		uma_zfree(udf_zone_node, unode);
1267 		vp->v_data = NULL;
1268 	}
1269 
1270 	return (0);
1271 }
1272 
1273 static int
1274 udf_vptofh(struct vop_vptofh_args *a)
1275 {
1276 	struct udf_node *node;
1277 	struct ifid *ifhp;
1278 
1279 	node = VTON(a->a_vp);
1280 	ifhp = (struct ifid *)a->a_fhp;
1281 	ifhp->ifid_len = sizeof(struct ifid);
1282 	ifhp->ifid_ino = node->hash_id;
1283 
1284 	return (0);
1285 }
1286 
1287 /*
1288  * Read the block and then set the data pointer to correspond with the
1289  * offset passed in.  Only read in at most 'size' bytes, and then set 'size'
1290  * to the number of bytes pointed to.  If 'size' is zero, try to read in a
1291  * whole extent.
1292  *
1293  * Note that *bp may be assigned error or not.
1294  *
1295  */
1296 static int
1297 udf_readatoffset(struct udf_node *node, int *size, off_t offset,
1298     struct buf **bp, uint8_t **data)
1299 {
1300 	struct udf_mnt *udfmp = node->udfmp;
1301 	struct vnode *vp = node->i_vnode;
1302 	struct file_entry *fentry;
1303 	struct buf *bp1;
1304 	uint32_t max_size;
1305 	daddr_t sector;
1306 	off_t off;
1307 	int adj_size;
1308 	int error;
1309 
1310 	/*
1311 	 * This call is made *not* only to detect UDF_INVALID_BMAP case,
1312 	 * max_size is used as an ad-hoc read-ahead hint for "normal" case.
1313 	 */
1314 	error = udf_bmap_internal(node, offset, &sector, &max_size);
1315 	if (error == UDF_INVALID_BMAP) {
1316 		/*
1317 		 * This error means that the file *data* is stored in the
1318 		 * allocation descriptor field of the file entry.
1319 		 */
1320 		fentry = node->fentry;
1321 		*data = &fentry->data[le32toh(fentry->l_ea)];
1322 		*size = le32toh(fentry->l_ad);
1323 		if (offset >= *size)
1324 			*size = 0;
1325 		else {
1326 			*data += offset;
1327 			*size -= offset;
1328 		}
1329 		return (0);
1330 	} else if (error != 0) {
1331 		return (error);
1332 	}
1333 
1334 	/* Adjust the size so that it is within range */
1335 	if (*size == 0 || *size > max_size)
1336 		*size = max_size;
1337 
1338 	/*
1339 	 * Because we will read starting at block boundary, we need to adjust
1340 	 * how much we need to read so that all promised data is in.
1341 	 * Also, we can't promise to read more than MAXBSIZE bytes starting
1342 	 * from block boundary, so adjust what we promise too.
1343 	 */
1344 	off = blkoff(udfmp, offset);
1345 	*size = min(*size, MAXBSIZE - off);
1346 	adj_size = (*size + off + udfmp->bmask) & ~udfmp->bmask;
1347 	*bp = NULL;
1348 	if ((error = bread(vp, lblkno(udfmp, offset), adj_size, NOCRED, bp))) {
1349 		printf("warning: udf_readlblks returned error %d\n", error);
1350 		/* note: *bp may be non-NULL */
1351 		return (error);
1352 	}
1353 
1354 	bp1 = *bp;
1355 	*data = (uint8_t *)&bp1->b_data[offset & udfmp->bmask];
1356 	return (0);
1357 }
1358 
1359 /*
1360  * Translate a file offset into a logical block and then into a physical
1361  * block.
1362  * max_size - maximum number of bytes that can be read starting from given
1363  * offset, rather than beginning of calculated sector number
1364  */
1365 static int
1366 udf_bmap_internal(struct udf_node *node, off_t offset, daddr_t *sector,
1367     uint32_t *max_size)
1368 {
1369 	struct udf_mnt *udfmp;
1370 	struct file_entry *fentry;
1371 	void *icb;
1372 	struct icb_tag *tag;
1373 	uint32_t icblen = 0;
1374 	daddr_t lsector;
1375 	int ad_offset, ad_num = 0;
1376 	int i, p_offset;
1377 
1378 	udfmp = node->udfmp;
1379 	fentry = node->fentry;
1380 	tag = &fentry->icbtag;
1381 
1382 	switch (le16toh(tag->strat_type)) {
1383 	case 4:
1384 		break;
1385 
1386 	case 4096:
1387 		printf("Cannot deal with strategy4096 yet!\n");
1388 		return (ENODEV);
1389 
1390 	default:
1391 		printf("Unknown strategy type %d\n", tag->strat_type);
1392 		return (ENODEV);
1393 	}
1394 
1395 	switch (le16toh(tag->flags) & 0x7) {
1396 	case 0:
1397 		/*
1398 		 * The allocation descriptor field is filled with short_ad's.
1399 		 * If the offset is beyond the current extent, look for the
1400 		 * next extent.
1401 		 */
1402 		do {
1403 			offset -= icblen;
1404 			ad_offset = sizeof(struct short_ad) * ad_num;
1405 			if (ad_offset > le32toh(fentry->l_ad)) {
1406 				printf("File offset out of bounds\n");
1407 				return (EINVAL);
1408 			}
1409 			icb = GETICB(short_ad, fentry,
1410 			    le32toh(fentry->l_ea) + ad_offset);
1411 			icblen = GETICBLEN(short_ad, icb);
1412 			ad_num++;
1413 		} while(offset >= icblen);
1414 
1415 		lsector = (offset  >> udfmp->bshift) +
1416 		    le32toh(((struct short_ad *)(icb))->pos);
1417 
1418 		*max_size = icblen - offset;
1419 
1420 		break;
1421 	case 1:
1422 		/*
1423 		 * The allocation descriptor field is filled with long_ad's
1424 		 * If the offset is beyond the current extent, look for the
1425 		 * next extent.
1426 		 */
1427 		do {
1428 			offset -= icblen;
1429 			ad_offset = sizeof(struct long_ad) * ad_num;
1430 			if (ad_offset > le32toh(fentry->l_ad)) {
1431 				printf("File offset out of bounds\n");
1432 				return (EINVAL);
1433 			}
1434 			icb = GETICB(long_ad, fentry,
1435 			    le32toh(fentry->l_ea) + ad_offset);
1436 			icblen = GETICBLEN(long_ad, icb);
1437 			ad_num++;
1438 		} while(offset >= icblen);
1439 
1440 		lsector = (offset >> udfmp->bshift) +
1441 		    le32toh(((struct long_ad *)(icb))->loc.lb_num);
1442 
1443 		*max_size = icblen - offset;
1444 
1445 		break;
1446 	case 3:
1447 		/*
1448 		 * This type means that the file *data* is stored in the
1449 		 * allocation descriptor field of the file entry.
1450 		 */
1451 		*max_size = 0;
1452 		*sector = node->hash_id + udfmp->part_start;
1453 
1454 		return (UDF_INVALID_BMAP);
1455 	case 2:
1456 		/* DirectCD does not use extended_ad's */
1457 	default:
1458 		printf("Unsupported allocation descriptor %d\n",
1459 		       tag->flags & 0x7);
1460 		return (ENODEV);
1461 	}
1462 
1463 	*sector = lsector + udfmp->part_start;
1464 
1465 	/*
1466 	 * Check the sparing table.  Each entry represents the beginning of
1467 	 * a packet.
1468 	 */
1469 	if (udfmp->s_table != NULL) {
1470 		for (i = 0; i< udfmp->s_table_entries; i++) {
1471 			p_offset =
1472 			    lsector - le32toh(udfmp->s_table->entries[i].org);
1473 			if ((p_offset < udfmp->p_sectors) && (p_offset >= 0)) {
1474 				*sector =
1475 				   le32toh(udfmp->s_table->entries[i].map) +
1476 				    p_offset;
1477 				break;
1478 			}
1479 		}
1480 	}
1481 
1482 	return (0);
1483 }
1484