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udf_readwrite.c revision 1.1.6.6
      1 /* $NetBSD: udf_readwrite.c,v 1.1.6.6 2009/01/17 13:29:17 mjf Exp $ */
      2 
      3 /*
      4  * Copyright (c) 2007, 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_readwrite.c,v 1.1.6.6 2009/01/17 13:29:17 mjf Exp $");
     32 #endif /* not lint */
     33 
     34 
     35 #if defined(_KERNEL_OPT)
     36 #include "opt_compat_netbsd.h"
     37 #endif
     38 
     39 #include <sys/param.h>
     40 #include <sys/systm.h>
     41 #include <sys/sysctl.h>
     42 #include <sys/namei.h>
     43 #include <sys/proc.h>
     44 #include <sys/kernel.h>
     45 #include <sys/vnode.h>
     46 #include <miscfs/genfs/genfs_node.h>
     47 #include <sys/mount.h>
     48 #include <sys/buf.h>
     49 #include <sys/file.h>
     50 #include <sys/device.h>
     51 #include <sys/disklabel.h>
     52 #include <sys/ioctl.h>
     53 #include <sys/malloc.h>
     54 #include <sys/dirent.h>
     55 #include <sys/stat.h>
     56 #include <sys/conf.h>
     57 #include <sys/kauth.h>
     58 #include <sys/kthread.h>
     59 #include <dev/clock_subr.h>
     60 
     61 #include <fs/udf/ecma167-udf.h>
     62 #include <fs/udf/udf_mount.h>
     63 
     64 #include "udf.h"
     65 #include "udf_subr.h"
     66 #include "udf_bswap.h"
     67 
     68 
     69 #define VTOI(vnode) ((struct udf_node *) vnode->v_data)
     70 
     71 /* --------------------------------------------------------------------- */
     72 
     73 void
     74 udf_fixup_fid_block(uint8_t *blob, int lb_size,
     75 	int rfix_pos, int max_rfix_pos, uint32_t lb_num)
     76 {
     77 	struct fileid_desc *fid;
     78 	uint8_t *fid_pos;
     79 	int fid_len, found;
     80 
     81 	/* needs to be word aligned */
     82 	KASSERT(rfix_pos % 4 == 0);
     83 
     84 	/* first resync with the FID stream !!! */
     85 	found = 0;
     86 	while (rfix_pos + sizeof(struct desc_tag) <= max_rfix_pos) {
     87 		fid_pos = blob + rfix_pos;
     88 		fid = (struct fileid_desc *) fid_pos;
     89 		if (udf_rw16(fid->tag.id) == TAGID_FID) {
     90 			if (udf_check_tag((union dscrptr *) fid) == 0)
     91 				found = 1;
     92 		}
     93 		if (found)
     94 			break;
     95 		/* try next location; can only be 4 bytes aligned */
     96 		rfix_pos += 4;
     97 	}
     98 
     99 	/* walk over the fids */
    100 	fid_pos = blob + rfix_pos;
    101 	while (rfix_pos + sizeof(struct desc_tag) <= max_rfix_pos) {
    102 		fid = (struct fileid_desc *) fid_pos;
    103 		if (udf_rw16(fid->tag.id) != TAGID_FID) {
    104 			/* end of FID stream; end of directory or currupted */
    105 			break;
    106 		}
    107 
    108 		/* update sector number and recalculate checkum */
    109 		fid->tag.tag_loc = udf_rw32(lb_num);
    110 		udf_validate_tag_sum((union dscrptr *) fid);
    111 
    112 		/* if the FID crosses the memory, we're done! */
    113 		if (rfix_pos + UDF_FID_SIZE >= max_rfix_pos)
    114 			break;
    115 
    116 		fid_len = udf_fidsize(fid);
    117 		fid_pos  += fid_len;
    118 		rfix_pos += fid_len;
    119 	}
    120 }
    121 
    122 
    123 void
    124 udf_fixup_internal_extattr(uint8_t *blob, uint32_t lb_num)
    125 {
    126 	struct desc_tag        *tag;
    127 	struct file_entry      *fe;
    128 	struct extfile_entry   *efe;
    129 	struct extattrhdr_desc *eahdr;
    130 	int l_ea;
    131 
    132 	/* get information from fe/efe */
    133 	tag = (struct desc_tag *) blob;
    134 	switch (udf_rw16(tag->id)) {
    135 	case TAGID_FENTRY :
    136 		fe = (struct file_entry *) blob;
    137 		l_ea  = udf_rw32(fe->l_ea);
    138 		eahdr = (struct extattrhdr_desc *) fe->data;
    139 		break;
    140 	case TAGID_EXTFENTRY :
    141 		efe = (struct extfile_entry *) blob;
    142 		l_ea  = udf_rw32(efe->l_ea);
    143 		eahdr = (struct extattrhdr_desc *) efe->data;
    144 		break;
    145 	case TAGID_INDIRECTENTRY :
    146 	case TAGID_ALLOCEXTENT :
    147 	case TAGID_EXTATTR_HDR :
    148 		return;
    149 	default:
    150 		panic("%s: passed bad tag\n", __func__);
    151 	}
    152 
    153 	/* something recorded here? (why am i called?) */
    154 	if (l_ea == 0)
    155 		return;
    156 
    157 #if 0
    158 	/* check extended attribute tag */
    159 	/* TODO XXX what to do when we encounter an error here? */
    160 	error = udf_check_tag(eahdr);
    161 	if (error)
    162 		return;	/* for now */
    163 	if (udf_rw16(eahdr->tag.id) != TAGID_EXTATTR_HDR)
    164 		return;	/* for now */
    165 	error = udf_check_tag_payload(eahdr, sizeof(struct extattrhdr_desc));
    166 	if (error)
    167 		return; /* for now */
    168 #endif
    169 
    170 	DPRINTF(EXTATTR, ("node fixup: found %d bytes of extended attributes\n",
    171 		l_ea));
    172 
    173 	/* fixup eahdr tag */
    174 	eahdr->tag.tag_loc = udf_rw32(lb_num);
    175 	udf_validate_tag_and_crc_sums((union dscrptr *) eahdr);
    176 }
    177 
    178 
    179 void
    180 udf_fixup_node_internals(struct udf_mount *ump, uint8_t *blob, int udf_c_type)
    181 {
    182 	struct desc_tag *tag, *sbm_tag;
    183 	struct file_entry *fe;
    184 	struct extfile_entry *efe;
    185 	struct alloc_ext_entry *ext;
    186 	uint32_t lb_size, lb_num;
    187 	uint32_t intern_pos, max_intern_pos;
    188 	int icbflags, addr_type, file_type, intern, has_fids, has_sbm, l_ea;
    189 
    190 	lb_size = udf_rw32(ump->logical_vol->lb_size);
    191 	/* if its not a node we're done */
    192 	if (udf_c_type != UDF_C_NODE)
    193 		return;
    194 
    195 	/* NOTE this could also be done in write_internal */
    196 	/* start of a descriptor */
    197 	l_ea      = 0;
    198 	has_fids  = 0;
    199 	has_sbm   = 0;
    200 	intern    = 0;
    201 	file_type = 0;
    202 	max_intern_pos = intern_pos = lb_num = 0;	/* shut up gcc! */
    203 
    204 	tag = (struct desc_tag *) blob;
    205 	switch (udf_rw16(tag->id)) {
    206 	case TAGID_FENTRY :
    207 		fe = (struct file_entry *) tag;
    208 		l_ea = udf_rw32(fe->l_ea);
    209 		icbflags  = udf_rw16(fe->icbtag.flags);
    210 		addr_type = (icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK);
    211 		file_type = fe->icbtag.file_type;
    212 		intern = (addr_type == UDF_ICB_INTERN_ALLOC);
    213 		intern_pos  = UDF_FENTRY_SIZE + l_ea;
    214 		max_intern_pos = intern_pos + udf_rw64(fe->inf_len);
    215 		lb_num = udf_rw32(fe->tag.tag_loc);
    216 		break;
    217 	case TAGID_EXTFENTRY :
    218 		efe = (struct extfile_entry *) tag;
    219 		l_ea = udf_rw32(efe->l_ea);
    220 		icbflags  = udf_rw16(efe->icbtag.flags);
    221 		addr_type = (icbflags & UDF_ICB_TAG_FLAGS_ALLOC_MASK);
    222 		file_type = efe->icbtag.file_type;
    223 		intern = (addr_type == UDF_ICB_INTERN_ALLOC);
    224 		intern_pos  = UDF_EXTFENTRY_SIZE + l_ea;
    225 		max_intern_pos = intern_pos + udf_rw64(efe->inf_len);
    226 		lb_num = udf_rw32(efe->tag.tag_loc);
    227 		break;
    228 	case TAGID_INDIRECTENTRY :
    229 	case TAGID_EXTATTR_HDR :
    230 		break;
    231 	case TAGID_ALLOCEXTENT :
    232 		/* force crclen to 8 for UDF version < 2.01 */
    233 		ext = (struct alloc_ext_entry *) tag;
    234 		if (udf_rw16(ump->logvol_info->min_udf_readver) <= 0x200)
    235 			ext->tag.desc_crc_len = udf_rw16(8);
    236 		break;
    237 	default:
    238 		panic("%s: passed bad tag\n", __func__);
    239 		break;
    240 	}
    241 
    242 	/* determine what to fix if its internally recorded */
    243 	if (intern) {
    244 		has_fids = (file_type == UDF_ICB_FILETYPE_DIRECTORY) ||
    245 			   (file_type == UDF_ICB_FILETYPE_STREAMDIR);
    246 		has_sbm  = (file_type == UDF_ICB_FILETYPE_META_BITMAP);
    247 	}
    248 
    249 	/* fixup internal extended attributes if present */
    250 	if (l_ea)
    251 		udf_fixup_internal_extattr(blob, lb_num);
    252 
    253 	/* fixup fids lb numbers */
    254 	if (has_fids)
    255 		udf_fixup_fid_block(blob, lb_size, intern_pos,
    256 			max_intern_pos, lb_num);
    257 
    258 	/* fixup space bitmap descriptor */
    259 	if (has_sbm) {
    260 		sbm_tag = (struct desc_tag *) (blob + intern_pos);
    261 		sbm_tag->tag_loc = tag->tag_loc;
    262 		udf_validate_tag_and_crc_sums((uint8_t *) sbm_tag);
    263 	}
    264 
    265 	udf_validate_tag_and_crc_sums(blob);
    266 }
    267 
    268 /* --------------------------------------------------------------------- */
    269 
    270 /*
    271  * Set of generic descriptor readers and writers and their helper functions.
    272  * Descriptors inside `logical space' i.e. inside logically mapped partitions
    273  * can never be longer than one logical sector.
    274  *
    275  * NOTE that these functions *can* be used by the sheduler backends to read
    276  * node descriptors too.
    277  *
    278  * For reading, the size of allocated piece is returned in multiple of sector
    279  * size due to udf_calc_udf_malloc_size().
    280  */
    281 
    282 
    283 /* SYNC reading of n blocks from specified sector */
    284 /* NOTE only used by udf_read_phys_dscr */
    285 static int
    286 udf_read_phys_sectors(struct udf_mount *ump, int what, void *blob,
    287 	uint32_t start, uint32_t sectors)
    288 {
    289 	struct buf *buf, *nestbuf;
    290 	uint32_t buf_offset;
    291 	off_t lblkno, rblkno;
    292 	int sector_size = ump->discinfo.sector_size;
    293 	int blks = sector_size / DEV_BSIZE;
    294 	int piece;
    295 	int error;
    296 
    297 	DPRINTF(READ, ("udf_intbreadn() : sectors = %d, sector_size = %d\n",
    298 		sectors, sector_size));
    299 	buf = getiobuf(ump->devvp, true);
    300 	buf->b_flags    = B_READ;
    301 	buf->b_cflags   = BC_BUSY;	/* needed? */
    302 	buf->b_iodone   = NULL;
    303 	buf->b_data     = blob;
    304 	buf->b_bcount   = sectors * sector_size;
    305 	buf->b_resid    = buf->b_bcount;
    306 	buf->b_bufsize  = buf->b_bcount;
    307 	buf->b_private  = NULL;	/* not needed yet */
    308 	BIO_SETPRIO(buf, BPRIO_DEFAULT);
    309 	buf->b_lblkno   = buf->b_blkno = buf->b_rawblkno = start * blks;
    310 	buf->b_proc     = NULL;
    311 
    312 	error = 0;
    313 	buf_offset = 0;
    314 	rblkno = start;
    315 	lblkno = 0;
    316 	while ((sectors > 0) && (error == 0)) {
    317 		piece = MIN(MAXPHYS/sector_size, sectors);
    318 		DPRINTF(READ, ("read in %d + %d\n", (uint32_t) rblkno, piece));
    319 
    320 		nestbuf = getiobuf(NULL, true);
    321 		nestiobuf_setup(buf, nestbuf, buf_offset, piece * sector_size);
    322 		/* nestbuf is B_ASYNC */
    323 
    324 		/* identify this nestbuf */
    325 		nestbuf->b_lblkno   = lblkno;
    326 
    327 		/* CD shedules on raw blkno */
    328 		nestbuf->b_blkno      = rblkno * blks;
    329 		nestbuf->b_proc       = NULL;
    330 		nestbuf->b_rawblkno   = rblkno * blks;
    331 		nestbuf->b_udf_c_type = what;
    332 
    333 		udf_discstrat_queuebuf(ump, nestbuf);
    334 
    335 		lblkno     += piece;
    336 		rblkno     += piece;
    337 		buf_offset += piece * sector_size;
    338 		sectors    -= piece;
    339 	}
    340 	error = biowait(buf);
    341 	putiobuf(buf);
    342 
    343 	return error;
    344 }
    345 
    346 
    347 /* synchronous generic descriptor read */
    348 int
    349 udf_read_phys_dscr(struct udf_mount *ump, uint32_t sector,
    350 		    struct malloc_type *mtype, union dscrptr **dstp)
    351 {
    352 	union dscrptr *dst, *new_dst;
    353 	uint8_t *pos;
    354 	int sectors, dscrlen;
    355 	int i, error, sector_size;
    356 
    357 	sector_size = ump->discinfo.sector_size;
    358 
    359 	*dstp = dst = NULL;
    360 	dscrlen = sector_size;
    361 
    362 	/* read initial piece */
    363 	dst = malloc(sector_size, mtype, M_WAITOK);
    364 	error = udf_read_phys_sectors(ump, UDF_C_DSCR, dst, sector, 1);
    365 	DPRINTFIF(DESCRIPTOR, error, ("read error (%d)\n", error));
    366 
    367 	if (!error) {
    368 		/* check if its a valid tag */
    369 		error = udf_check_tag(dst);
    370 		if (error) {
    371 			/* check if its an empty block */
    372 			pos = (uint8_t *) dst;
    373 			for (i = 0; i < sector_size; i++, pos++) {
    374 				if (*pos) break;
    375 			}
    376 			if (i == sector_size) {
    377 				/* return no error but with no dscrptr */
    378 				/* dispose first block */
    379 				free(dst, mtype);
    380 				return 0;
    381 			}
    382 		}
    383 		/* calculate descriptor size */
    384 		dscrlen = udf_tagsize(dst, sector_size);
    385 	}
    386 	DPRINTFIF(DESCRIPTOR, error, ("bad tag checksum\n"));
    387 
    388 	if (!error && (dscrlen > sector_size)) {
    389 		DPRINTF(DESCRIPTOR, ("multi block descriptor read\n"));
    390 		/*
    391 		 * Read the rest of descriptor. Since it is only used at mount
    392 		 * time its overdone to define and use a specific udf_intbreadn
    393 		 * for this alone.
    394 		 */
    395 
    396 		new_dst = realloc(dst, dscrlen, mtype, M_WAITOK);
    397 		if (new_dst == NULL) {
    398 			free(dst, mtype);
    399 			return ENOMEM;
    400 		}
    401 		dst = new_dst;
    402 
    403 		sectors = (dscrlen + sector_size -1) / sector_size;
    404 		DPRINTF(DESCRIPTOR, ("dscrlen = %d (%d blk)\n", dscrlen, sectors));
    405 
    406 		pos = (uint8_t *) dst + sector_size;
    407 		error = udf_read_phys_sectors(ump, UDF_C_DSCR, pos,
    408 				sector + 1, sectors-1);
    409 
    410 		DPRINTFIF(DESCRIPTOR, error, ("read error on multi (%d)\n",
    411 		    error));
    412 	}
    413 	if (!error) {
    414 		error = udf_check_tag_payload(dst, dscrlen);
    415 		DPRINTFIF(DESCRIPTOR, error, ("bad payload check sum\n"));
    416 	}
    417 	if (error && dst) {
    418 		free(dst, mtype);
    419 		dst = NULL;
    420 	}
    421 	*dstp = dst;
    422 
    423 	return error;
    424 }
    425 
    426 
    427 static void
    428 udf_write_phys_buf(struct udf_mount *ump, int what, struct buf *buf)
    429 {
    430 	struct buf *nestbuf;
    431 	uint32_t buf_offset;
    432 	off_t lblkno, rblkno;
    433 	int sector_size = ump->discinfo.sector_size;
    434 	int blks = sector_size / DEV_BSIZE;
    435 	uint32_t sectors;
    436 	int piece;
    437 	int error;
    438 
    439 	sectors = buf->b_bcount / sector_size;
    440 	DPRINTF(WRITE, ("udf_intbwriten() : sectors = %d, sector_size = %d\n",
    441 		sectors, sector_size));
    442 
    443 	/* don't forget to increase pending count for the bwrite itself */
    444 /* panic("NO WRITING\n"); */
    445 	if (buf->b_vp) {
    446 		mutex_enter(&buf->b_vp->v_interlock);
    447 		buf->b_vp->v_numoutput++;
    448 		mutex_exit(&buf->b_vp->v_interlock);
    449 	}
    450 
    451 	error = 0;
    452 	buf_offset = 0;
    453 	rblkno = buf->b_blkno / blks;
    454 	lblkno = 0;
    455 	while ((sectors > 0) && (error == 0)) {
    456 		piece = MIN(MAXPHYS/sector_size, sectors);
    457 		DPRINTF(WRITE, ("write out %d + %d\n",
    458 		    (uint32_t) rblkno, piece));
    459 
    460 		nestbuf = getiobuf(NULL, true);
    461 		nestiobuf_setup(buf, nestbuf, buf_offset, piece * sector_size);
    462 		/* nestbuf is B_ASYNC */
    463 
    464 		/* identify this nestbuf */
    465 		nestbuf->b_lblkno   = lblkno;
    466 
    467 		/* CD shedules on raw blkno */
    468 		nestbuf->b_blkno      = rblkno * blks;
    469 		nestbuf->b_proc       = NULL;
    470 		nestbuf->b_rawblkno   = rblkno * blks;
    471 		nestbuf->b_udf_c_type = what;
    472 
    473 		udf_discstrat_queuebuf(ump, nestbuf);
    474 
    475 		lblkno     += piece;
    476 		rblkno     += piece;
    477 		buf_offset += piece * sector_size;
    478 		sectors    -= piece;
    479 	}
    480 }
    481 
    482 
    483 /* synchronous generic descriptor write */
    484 int
    485 udf_write_phys_dscr_sync(struct udf_mount *ump, struct udf_node *udf_node, int what,
    486 		     union dscrptr *dscr, uint32_t sector, uint32_t logsector)
    487 {
    488 	struct vnode *vp;
    489 	struct buf *buf;
    490 	int sector_size = ump->discinfo.sector_size;
    491 	int blks = sector_size / DEV_BSIZE;
    492 	int dscrlen;
    493 	int error;
    494 
    495 	/* set sector number in the descriptor and validate */
    496 	dscr->tag.tag_loc = udf_rw32(logsector);
    497 	udf_validate_tag_and_crc_sums(dscr);
    498 
    499 	/* calculate descriptor size */
    500 	dscrlen = udf_tagsize(dscr, sector_size);
    501 
    502 	/* get transfer buffer */
    503 	vp = udf_node ? udf_node->vnode : ump->devvp;
    504 	buf = getiobuf(vp, true);
    505 	buf->b_flags    = B_WRITE;
    506 	buf->b_cflags   = BC_BUSY;	/* needed? */
    507 	buf->b_iodone   = NULL;
    508 	buf->b_data     = (void *) dscr;
    509 	buf->b_bcount   = dscrlen;
    510 	buf->b_resid    = buf->b_bcount;
    511 	buf->b_bufsize  = buf->b_bcount;
    512 	buf->b_private  = NULL;	/* not needed yet */
    513 	BIO_SETPRIO(buf, BPRIO_DEFAULT);
    514 	buf->b_lblkno   = buf->b_blkno = buf->b_rawblkno = sector * blks;
    515 	buf->b_proc     = NULL;
    516 
    517 	/* do the write, wait and return error */
    518 	udf_write_phys_buf(ump, what, buf);
    519 	error = biowait(buf);
    520 	putiobuf(buf);
    521 
    522 	return error;
    523 }
    524 
    525 
    526 /* asynchronous generic descriptor write */
    527 int
    528 udf_write_phys_dscr_async(struct udf_mount *ump, struct udf_node *udf_node,
    529 		      int what, union dscrptr *dscr,
    530 		      uint32_t sector, uint32_t logsector,
    531 		      void (*dscrwr_callback)(struct buf *))
    532 {
    533 	struct vnode *vp;
    534 	struct buf *buf;
    535 	int dscrlen;
    536 	int sector_size = ump->discinfo.sector_size;
    537 	int blks = sector_size / DEV_BSIZE;
    538 
    539 	KASSERT(dscrwr_callback);
    540 	DPRINTF(NODE, ("udf_write_phys_dscr_async() called\n"));
    541 
    542 	/* set sector number in the descriptor and validate */
    543 	dscr->tag.tag_loc = udf_rw32(logsector);
    544 	udf_validate_tag_and_crc_sums(dscr);
    545 
    546 	/* calculate descriptor size */
    547 	dscrlen = udf_tagsize(dscr, sector_size);
    548 
    549 	/* get transfer buffer */
    550 	vp = udf_node ? udf_node->vnode : ump->devvp;
    551 	buf = getiobuf(vp, true);
    552 	buf->b_flags    = B_WRITE; // | B_ASYNC;
    553 	buf->b_cflags   = BC_BUSY;
    554 	buf->b_iodone	= dscrwr_callback;
    555 	buf->b_data     = dscr;
    556 	buf->b_bcount   = dscrlen;
    557 	buf->b_resid    = buf->b_bcount;
    558 	buf->b_bufsize  = buf->b_bcount;
    559 	buf->b_private  = NULL;	/* not needed yet */
    560 	BIO_SETPRIO(buf, BPRIO_DEFAULT);
    561 	buf->b_lblkno   = buf->b_blkno = buf->b_rawblkno = sector * blks;
    562 	buf->b_proc     = NULL;
    563 
    564 	/* do the write and return no error */
    565 	udf_write_phys_buf(ump, what, buf);
    566 	return 0;
    567 }
    568 
    569 /* --------------------------------------------------------------------- */
    570 
    571 /* disc strategy dispatchers */
    572 
    573 int
    574 udf_create_logvol_dscr(struct udf_mount *ump, struct udf_node *udf_node, struct long_ad *icb,
    575 	union dscrptr **dscrptr)
    576 {
    577 	struct udf_strategy *strategy = ump->strategy;
    578 	struct udf_strat_args args;
    579 	int error;
    580 
    581 	KASSERT(strategy);
    582 	args.ump  = ump;
    583 	args.udf_node = udf_node;
    584 	args.icb  = icb;
    585 	args.dscr = NULL;
    586 
    587 	error = (strategy->create_logvol_dscr)(&args);
    588 	*dscrptr = args.dscr;
    589 
    590 	return error;
    591 }
    592 
    593 
    594 void
    595 udf_free_logvol_dscr(struct udf_mount *ump, struct long_ad *icb,
    596 	void *dscr)
    597 {
    598 	struct udf_strategy *strategy = ump->strategy;
    599 	struct udf_strat_args args;
    600 
    601 	KASSERT(strategy);
    602 	args.ump  = ump;
    603 	args.icb  = icb;
    604 	args.dscr = dscr;
    605 
    606 	(strategy->free_logvol_dscr)(&args);
    607 }
    608 
    609 
    610 int
    611 udf_read_logvol_dscr(struct udf_mount *ump, struct long_ad *icb,
    612 	union dscrptr **dscrptr)
    613 {
    614 	struct udf_strategy *strategy = ump->strategy;
    615 	struct udf_strat_args args;
    616 	int error;
    617 
    618 	KASSERT(strategy);
    619 	args.ump  = ump;
    620 	args.icb  = icb;
    621 	args.dscr = NULL;
    622 
    623 	error = (strategy->read_logvol_dscr)(&args);
    624 	*dscrptr = args.dscr;
    625 
    626 	return error;
    627 }
    628 
    629 
    630 int
    631 udf_write_logvol_dscr(struct udf_node *udf_node, union dscrptr *dscr,
    632 	struct long_ad *icb, int waitfor)
    633 {
    634 	struct udf_strategy *strategy = udf_node->ump->strategy;
    635 	struct udf_strat_args args;
    636 	int error;
    637 
    638 	KASSERT(strategy);
    639 	args.ump      = udf_node->ump;
    640 	args.udf_node = udf_node;
    641 	args.icb      = icb;
    642 	args.dscr     = dscr;
    643 	args.waitfor  = waitfor;
    644 
    645 	error = (strategy->write_logvol_dscr)(&args);
    646 	return error;
    647 }
    648 
    649 
    650 void
    651 udf_discstrat_queuebuf(struct udf_mount *ump, struct buf *nestbuf)
    652 {
    653 	struct udf_strategy *strategy = ump->strategy;
    654 	struct udf_strat_args args;
    655 
    656 	KASSERT(strategy);
    657 	args.ump = ump;
    658 	args.nestbuf = nestbuf;
    659 
    660 	(strategy->queuebuf)(&args);
    661 }
    662 
    663 
    664 void
    665 udf_discstrat_init(struct udf_mount *ump)
    666 {
    667 	struct udf_strategy *strategy = ump->strategy;
    668 	struct udf_strat_args args;
    669 
    670 	KASSERT(strategy);
    671 	args.ump = ump;
    672 	(strategy->discstrat_init)(&args);
    673 }
    674 
    675 
    676 void udf_discstrat_finish(struct udf_mount *ump)
    677 {
    678 	struct udf_strategy *strategy = ump->strategy;
    679 	struct udf_strat_args args;
    680 
    681 	/* strategy might not have been set, so ignore if not set */
    682 	if (strategy) {
    683 		args.ump = ump;
    684 		(strategy->discstrat_finish)(&args);
    685 	}
    686 }
    687 
    688 /* --------------------------------------------------------------------- */
    689 
    690