1/* $NetBSD: isadma_bounce.c,v 1.19 2022/01/22 15:10:30 skrll Exp $ */ 2/* NetBSD: isadma_bounce.c,v 1.2 2000/06/01 05:49:36 thorpej Exp */ 3 4/*- 5 * Copyright (c) 1996, 1997, 1998, 2000 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 10 * NASA Ames Research Center. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 35 36__KERNEL_RCSID(0, "$NetBSD: isadma_bounce.c,v 1.19 2022/01/22 15:10:30 skrll Exp $"); 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/syslog.h> 41#include <sys/device.h> 42#include <sys/kmem.h> 43#include <sys/proc.h> 44#include <sys/mbuf.h> 45 46#define _ARC_BUS_DMA_PRIVATE 47#include <sys/bus.h> 48 49#include <dev/isa/isareg.h> 50#include <dev/isa/isavar.h> 51 52#include <uvm/uvm_extern.h> 53 54/* 55 * Cookie used by bouncing ISA DMA. A pointer to one of these is stashed 56 * in the DMA map. 57 */ 58struct isadma_bounce_cookie { 59 int id_flags; /* flags; see below */ 60 61 /* 62 * Information about the original buffer used during 63 * DMA map syncs. Note that origbuflen is only used 64 * for ID_BUFTYPE_LINEAR. 65 */ 66 void *id_origbuf; /* pointer to orig buffer if 67 bouncing */ 68 bus_size_t id_origbuflen; /* ...and size */ 69 int id_buftype; /* type of buffer */ 70 71 void *id_bouncebuf; /* pointer to the bounce buffer */ 72 bus_size_t id_bouncebuflen; /* ...and size */ 73 int id_nbouncesegs; /* number of valid bounce segs */ 74 bus_dma_segment_t id_bouncesegs[1]; /* array of bounce buffer 75 physical memory segments */ 76}; 77 78/* id_flags */ 79#define ID_MIGHT_NEED_BOUNCE 0x01 /* map could need bounce buffers */ 80#define ID_HAS_BOUNCE 0x02 /* map currently has bounce buffers */ 81#define ID_IS_BOUNCING 0x04 /* map is bouncing current xfer */ 82 83/* id_buftype */ 84#define ID_BUFTYPE_INVALID 0 85#define ID_BUFTYPE_LINEAR 1 86#define ID_BUFTYPE_MBUF 2 87#define ID_BUFTYPE_UIO 3 88#define ID_BUFTYPE_RAW 4 89 90int isadma_bounce_dmamap_create(bus_dma_tag_t, bus_size_t, int, 91 bus_size_t, bus_size_t, int, bus_dmamap_t *); 92void isadma_bounce_dmamap_destroy(bus_dma_tag_t, bus_dmamap_t); 93int isadma_bounce_dmamap_load(bus_dma_tag_t, bus_dmamap_t, void *, 94 bus_size_t, struct proc *, int); 95int isadma_bounce_dmamap_load_mbuf(bus_dma_tag_t, bus_dmamap_t, 96 struct mbuf *, int); 97int isadma_bounce_dmamap_load_uio(bus_dma_tag_t, bus_dmamap_t, 98 struct uio *, int); 99int isadma_bounce_dmamap_load_raw(bus_dma_tag_t, bus_dmamap_t, 100 bus_dma_segment_t *, int, bus_size_t, int); 101void isadma_bounce_dmamap_unload(bus_dma_tag_t, bus_dmamap_t); 102void isadma_bounce_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, 103 bus_addr_t, bus_size_t, int); 104int isadma_bounce_dmamem_alloc(bus_dma_tag_t, bus_size_t, bus_size_t, 105 bus_size_t, bus_dma_segment_t *, int, int *, int); 106 107static int isadma_bounce_alloc_bouncebuf(bus_dma_tag_t, bus_dmamap_t, 108 bus_size_t, int); 109static void isadma_bounce_free_bouncebuf(bus_dma_tag_t, bus_dmamap_t); 110 111/* 112 * Returns true if the system memory configuration exceeds the 113 * capabilities of ISA DMA. 114 */ 115static bool 116isadma_bounce_check_range(bus_dma_tag_t const t) 117{ 118 return pmap_limits.avail_end > ISA_DMA_BOUNCE_THRESHOLD; 119} 120 121static int 122isadma_bounce_cookieflags(bus_dma_tag_t const t, bus_dmamap_t const map) 123{ 124 int cookieflags = 0; 125 126 /* 127 * ISA only has 24-bits of address space. This means 128 * we can't DMA to pages over 16M. In order to DMA to 129 * arbitrary buffers, we use "bounce buffers" - pages 130 * in memory below the 16M boundary. On DMA reads, 131 * DMA happens to the bounce buffers, and is copied into 132 * the caller's buffer. On writes, data is copied into 133 * the bounce buffer, and the DMA happens from those 134 * pages. To software using the DMA mapping interface, 135 * this looks simply like a data cache. 136 * 137 * If we have more than 16M of RAM in the system, we may 138 * need bounce buffers. We check and remember that here. 139 * 140 * ...or, there is an opposite case. The most segments 141 * a transfer will require is (maxxfer / PAGE_SIZE) + 1. If 142 * the caller can't handle that many segments (e.g. the 143 * ISA DMA controller), we may have to bounce it as well. 144 */ 145 if (isadma_bounce_check_range(t) || 146 ((map->_dm_size / PAGE_SIZE) + 1) > map->_dm_segcnt) { 147 cookieflags |= ID_MIGHT_NEED_BOUNCE; 148 } 149 return cookieflags; 150} 151 152static size_t 153isadma_bounce_cookiesize(bus_dmamap_t const map, int cookieflags) 154{ 155 size_t cookiesize = sizeof(struct isadma_bounce_cookie); 156 157 if (cookieflags & ID_MIGHT_NEED_BOUNCE) { 158 cookiesize += (sizeof(bus_dma_segment_t) * 159 (map->_dm_segcnt - 1)); 160 } 161 return cookiesize; 162} 163 164static int 165isadma_bounce_cookie_alloc(bus_dma_tag_t const t, bus_dmamap_t const map, 166 int const flags) 167{ 168 struct isadma_bounce_cookie *cookie; 169 int cookieflags = isadma_bounce_cookieflags(t, map); 170 171 if ((cookie = kmem_zalloc(isadma_bounce_cookiesize(map, cookieflags), 172 (flags & BUS_DMA_NOWAIT) ? KM_NOSLEEP : KM_SLEEP)) == NULL) { 173 return ENOMEM; 174 } 175 176 cookie->id_flags = cookieflags; 177 map->_dm_cookie = cookie; 178 179 return 0; 180} 181 182static void 183isadma_bounce_cookie_free(bus_dmamap_t const map) 184{ 185 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 186 187 if (cookie != NULL) { 188 kmem_free(map->_dm_cookie, 189 isadma_bounce_cookiesize(map, cookie->id_flags)); 190 map->_dm_cookie = NULL; 191 } 192} 193 194void 195isadma_bounce_tag_init(bus_dma_tag_t t) 196{ 197 /* 198 * Initialize the DMA tag used for ISA DMA. 199 */ 200 201 _bus_dma_tag_init(t); 202 203 t->_dmamap_create = isadma_bounce_dmamap_create; 204 t->_dmamap_destroy = isadma_bounce_dmamap_destroy; 205 t->_dmamap_load = isadma_bounce_dmamap_load; 206 t->_dmamap_load_mbuf = isadma_bounce_dmamap_load_mbuf; 207 t->_dmamap_load_uio = isadma_bounce_dmamap_load_uio; 208 t->_dmamap_load_raw = isadma_bounce_dmamap_load_raw; 209 t->_dmamap_unload = isadma_bounce_dmamap_unload; 210 t->_dmamap_sync = isadma_bounce_dmamap_sync; 211 t->_dmamem_alloc = isadma_bounce_dmamem_alloc; 212} 213 214/* 215 * Create an ISA DMA map. 216 */ 217int 218isadma_bounce_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments, 219 bus_size_t maxsegsz, bus_size_t boundary, int flags, bus_dmamap_t *dmamp) 220{ 221 struct isadma_bounce_cookie *cookie; 222 bus_dmamap_t map; 223 int error; 224 225 /* Call common function to create the basic map. */ 226 error = _bus_dmamap_create(t, size, nsegments, maxsegsz, boundary, 227 flags, dmamp); 228 if (error) 229 return error; 230 231 map = *dmamp; 232 map->_dm_cookie = NULL; 233 234 /* 235 * Allocate our cookie. 236 */ 237 if ((error = isadma_bounce_cookie_alloc(t, map, flags)) != 0) { 238 goto out; 239 } 240 cookie = map->_dm_cookie; 241 242 if (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) { 243 /* 244 * Allocate the bounce pages now if the caller 245 * wishes us to do so. 246 */ 247 if (flags & BUS_DMA_ALLOCNOW) { 248 error = isadma_bounce_alloc_bouncebuf(t, map, size, 249 flags); 250 } 251 } 252 253 out: 254 if (error) { 255 isadma_bounce_cookie_free(map); 256 _bus_dmamap_destroy(t, map); 257 } 258 return error; 259} 260 261/* 262 * Destroy an ISA DMA map. 263 */ 264void 265isadma_bounce_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map) 266{ 267 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 268 269 /* 270 * Free any bounce pages this map might hold. 271 */ 272 if (cookie->id_flags & ID_HAS_BOUNCE) 273 isadma_bounce_free_bouncebuf(t, map); 274 275 isadma_bounce_cookie_free(map); 276 _bus_dmamap_destroy(t, map); 277} 278 279/* 280 * Load an ISA DMA map with a linear buffer. 281 */ 282int 283isadma_bounce_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map, void *buf, 284 bus_size_t buflen, struct proc *p, int flags) 285{ 286 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 287 int error; 288 289 /* 290 * Make sure that on error condition we return "no valid mappings." 291 */ 292 map->dm_mapsize = 0; 293 map->dm_nsegs = 0; 294 295 /* 296 * Try to load the map the normal way. If this errors out, 297 * and we can bounce, we will. 298 */ 299 error = _bus_dmamap_load(t, map, buf, buflen, p, flags); 300 if (error == 0 || (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0) 301 return error; 302 303 /* 304 * First attempt failed; bounce it. 305 */ 306 307 /* 308 * Allocate bounce pages, if necessary. 309 */ 310 if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) { 311 error = isadma_bounce_alloc_bouncebuf(t, map, buflen, flags); 312 if (error) 313 return error; 314 } 315 316 /* 317 * Cache a pointer to the caller's buffer and load the DMA map 318 * with the bounce buffer. 319 */ 320 cookie->id_origbuf = buf; 321 cookie->id_origbuflen = buflen; 322 cookie->id_buftype = ID_BUFTYPE_LINEAR; 323 error = _bus_dmamap_load(t, map, cookie->id_bouncebuf, buflen, 324 p, flags); 325 if (error) { 326 /* 327 * Free the bounce pages, unless our resources 328 * are reserved for our exclusive use. 329 */ 330 if ((map->_dm_flags & BUS_DMA_ALLOCNOW) == 0) 331 isadma_bounce_free_bouncebuf(t, map); 332 return error; 333 } 334 335 /* ...so isadma_bounce_dmamap_sync() knows we're bouncing */ 336 cookie->id_flags |= ID_IS_BOUNCING; 337 return 0; 338} 339 340/* 341 * Like isadma_bounce_dmamap_load(), but for mbufs. 342 */ 343int 344isadma_bounce_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map, 345 struct mbuf *m0, int flags) 346{ 347 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 348 int error; 349 350 /* 351 * Make sure on error condition we return "no valid mappings." 352 */ 353 map->dm_mapsize = 0; 354 map->dm_nsegs = 0; 355 356#ifdef DIAGNOSTIC 357 if ((m0->m_flags & M_PKTHDR) == 0) 358 panic("isadma_bounce_dmamap_load_mbuf: no packet header"); 359#endif 360 361 if (m0->m_pkthdr.len > map->_dm_size) 362 return EINVAL; 363 364 /* 365 * Try to load the map the normal way. If this errors out, 366 * and we can bounce, we will. 367 */ 368 error = _bus_dmamap_load_mbuf(t, map, m0, flags); 369 if (error == 0 || (cookie->id_flags & ID_MIGHT_NEED_BOUNCE) == 0) 370 return error; 371 372 /* 373 * First attempt failed; bounce it. 374 */ 375 376 /* 377 * Allocate bounce pages, if necessary. 378 */ 379 if ((cookie->id_flags & ID_HAS_BOUNCE) == 0) { 380 error = isadma_bounce_alloc_bouncebuf(t, map, m0->m_pkthdr.len, 381 flags); 382 if (error) 383 return error; 384 } 385 386 /* 387 * Cache a pointer to the caller's buffer and load the DMA map 388 * with the bounce buffer. 389 */ 390 cookie->id_origbuf = m0; 391 cookie->id_origbuflen = m0->m_pkthdr.len; /* not really used */ 392 cookie->id_buftype = ID_BUFTYPE_MBUF; 393 error = _bus_dmamap_load(t, map, cookie->id_bouncebuf, 394 m0->m_pkthdr.len, NULL, flags); 395 if (error) { 396 /* 397 * Free the bounce pages, unless our resources 398 * are reserved for our exclusive use. 399 */ 400 if ((map->_dm_flags & BUS_DMA_ALLOCNOW) == 0) 401 isadma_bounce_free_bouncebuf(t, map); 402 return error; 403 } 404 405 /* ...so isadma_bounce_dmamap_sync() knows we're bouncing */ 406 cookie->id_flags |= ID_IS_BOUNCING; 407 return 0; 408} 409 410/* 411 * Like isadma_bounce_dmamap_load(), but for uios. 412 */ 413int 414isadma_bounce_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map, 415 struct uio *uio, int flags) 416{ 417 418 panic("isadma_bounce_dmamap_load_uio: not implemented"); 419} 420 421/* 422 * Like isadma_bounce_dmamap_load(), but for raw memory allocated with 423 * bus_dmamem_alloc(). 424 */ 425int 426isadma_bounce_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map, 427 bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags) 428{ 429 430 panic("isadma_bounce_dmamap_load_raw: not implemented"); 431} 432 433/* 434 * Unload an ISA DMA map. 435 */ 436void 437isadma_bounce_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map) 438{ 439 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 440 441 /* 442 * If we have bounce pages, free them, unless they're 443 * reserved for our exclusive use. 444 */ 445 if ((cookie->id_flags & ID_HAS_BOUNCE) && 446 (map->_dm_flags & BUS_DMA_ALLOCNOW) == 0) 447 isadma_bounce_free_bouncebuf(t, map); 448 449 cookie->id_flags &= ~ID_IS_BOUNCING; 450 cookie->id_buftype = ID_BUFTYPE_INVALID; 451 452 /* 453 * Do the generic bits of the unload. 454 */ 455 _bus_dmamap_unload(t, map); 456} 457 458/* 459 * Synchronize an ISA DMA map. 460 */ 461void 462isadma_bounce_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset, 463 bus_size_t len, int ops) 464{ 465 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 466 void (*sync)(bus_dma_tag_t, bus_dmamap_t, bus_addr_t, bus_size_t, int); 467 468 sync = _bus_dmamap_sync; 469 470 /* 471 * Mixing PRE and POST operations is not allowed. 472 */ 473 if ((ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)) != 0 && 474 (ops & (BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)) != 0) 475 panic("isadma_bounce_dmamap_sync: mix PRE and POST"); 476 477#ifdef DIAGNOSTIC 478 if ((ops & (BUS_DMASYNC_PREWRITE|BUS_DMASYNC_POSTREAD)) != 0) { 479 if (offset >= map->dm_mapsize) 480 panic("isadma_bounce_dmamap_sync: bad offset"); 481 if (len == 0 || (offset + len) > map->dm_mapsize) 482 panic("isadma_bounce_dmamap_sync: bad length"); 483 } 484#endif 485 486 /* 487 * If we're not bouncing, just drain the write buffer 488 * and flush cache. 489 */ 490 if ((cookie->id_flags & ID_IS_BOUNCING) == 0) { 491 ((*sync)(t, map, offset, len, ops)); 492 return; 493 } 494 495 /* 496 * XXX 497 * This should be needed in BUS_DMASYNC_POSTREAD case only, 498 * if _mips3_bus_dmamap_sync() used "Hit_Invalidate on POSTREAD", 499 * rather than "Hit_Write_Back_Invalidate on PREREAD". 500 */ 501 if (ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_POSTREAD)) 502 ((*sync)(t, map, offset, len, ops)); 503 504 switch (cookie->id_buftype) { 505 case ID_BUFTYPE_LINEAR: 506 /* 507 * Nothing to do for pre-read. 508 */ 509 510 if (ops & BUS_DMASYNC_PREWRITE) { 511 /* 512 * Copy the caller's buffer to the bounce buffer. 513 */ 514 memcpy((char *)cookie->id_bouncebuf + offset, 515 (char *)cookie->id_origbuf + offset, len); 516 } 517 518 if (ops & BUS_DMASYNC_POSTREAD) { 519 /* 520 * Copy the bounce buffer to the caller's buffer. 521 */ 522 memcpy((char *)cookie->id_origbuf + offset, 523 (char *)cookie->id_bouncebuf + offset, len); 524 } 525 526 /* 527 * Nothing to do for post-write. 528 */ 529 break; 530 531 case ID_BUFTYPE_MBUF: 532 { 533 struct mbuf *m, *m0 = cookie->id_origbuf; 534 bus_size_t minlen, moff; 535 536 /* 537 * Nothing to do for pre-read. 538 */ 539 540 if (ops & BUS_DMASYNC_PREWRITE) { 541 /* 542 * Copy the caller's buffer to the bounce buffer. 543 */ 544 m_copydata(m0, offset, len, 545 (char *)cookie->id_bouncebuf + offset); 546 } 547 548 if (ops & BUS_DMASYNC_POSTREAD) { 549 /* 550 * Copy the bounce buffer to the caller's buffer. 551 */ 552 for (moff = offset, m = m0; m != NULL && len != 0; 553 m = m->m_next) { 554 /* Find the beginning mbuf. */ 555 if (moff >= m->m_len) { 556 moff -= m->m_len; 557 continue; 558 } 559 560 /* 561 * Now at the first mbuf to sync; nail 562 * each one until we have exhausted the 563 * length. 564 */ 565 minlen = len < m->m_len - moff ? 566 len : m->m_len - moff; 567 568 memcpy(mtod(m, char *) + moff, 569 (char *)cookie->id_bouncebuf + offset, 570 minlen); 571 572 moff = 0; 573 len -= minlen; 574 offset += minlen; 575 } 576 } 577 578 /* 579 * Nothing to do for post-write. 580 */ 581 break; 582 } 583 584 case ID_BUFTYPE_UIO: 585 panic("isadma_bounce_dmamap_sync: ID_BUFTYPE_UIO"); 586 break; 587 588 case ID_BUFTYPE_RAW: 589 panic("isadma_bounce_dmamap_sync: ID_BUFTYPE_RAW"); 590 break; 591 592 case ID_BUFTYPE_INVALID: 593 panic("isadma_bounce_dmamap_sync: ID_BUFTYPE_INVALID"); 594 break; 595 596 default: 597 printf("unknown buffer type %d\n", cookie->id_buftype); 598 panic("isadma_bounce_dmamap_sync"); 599 } 600 601 if (ops & BUS_DMASYNC_PREWRITE) 602 ((*sync)(t, map, offset, len, ops)); 603} 604 605/* 606 * Allocate memory safe for ISA DMA. 607 */ 608int 609isadma_bounce_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, 610 bus_size_t alignment, bus_size_t boundary, bus_dma_segment_t *segs, 611 int nsegs, int *rsegs, int flags) 612{ 613 paddr_t high; 614 615 if (pmap_limits.avail_end > ISA_DMA_BOUNCE_THRESHOLD) 616 high = ISA_DMA_BOUNCE_THRESHOLD - 1; 617 else 618 high = pmap_limits.avail_end - 1; 619 620 return _bus_dmamem_alloc_range(t, size, alignment, boundary, 621 segs, nsegs, rsegs, flags, 0, high); 622} 623 624/********************************************************************** 625 * ISA DMA utility functions 626 **********************************************************************/ 627 628static int 629isadma_bounce_alloc_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map, 630 bus_size_t size, int flags) 631{ 632 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 633 int error = 0; 634 635 cookie->id_bouncebuflen = round_page(size); 636 error = isadma_bounce_dmamem_alloc(t, cookie->id_bouncebuflen, 637 PAGE_SIZE, map->_dm_boundary, cookie->id_bouncesegs, 638 map->_dm_segcnt, &cookie->id_nbouncesegs, flags); 639 if (error) 640 goto out; 641 error = _bus_dmamem_map(t, cookie->id_bouncesegs, 642 cookie->id_nbouncesegs, cookie->id_bouncebuflen, 643 (void **)&cookie->id_bouncebuf, flags); 644 645 out: 646 if (error) { 647 _bus_dmamem_free(t, cookie->id_bouncesegs, 648 cookie->id_nbouncesegs); 649 cookie->id_bouncebuflen = 0; 650 cookie->id_nbouncesegs = 0; 651 } else 652 cookie->id_flags |= ID_HAS_BOUNCE; 653 654 return error; 655} 656 657static void 658isadma_bounce_free_bouncebuf(bus_dma_tag_t t, bus_dmamap_t map) 659{ 660 struct isadma_bounce_cookie *cookie = map->_dm_cookie; 661 662 _bus_dmamem_unmap(t, cookie->id_bouncebuf, 663 cookie->id_bouncebuflen); 664 _bus_dmamem_free(t, cookie->id_bouncesegs, 665 cookie->id_nbouncesegs); 666 cookie->id_bouncebuflen = 0; 667 cookie->id_nbouncesegs = 0; 668 cookie->id_flags &= ~ID_HAS_BOUNCE; 669} 670