1 /* 2 * Copyright (c) 1997, 1998 Justin T. Gibbs. 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 * without modification, immediately at the beginning of the file. 11 * 2. The name of the author may not be used to endorse or promote products 12 * derived from this software without specific prior written permission. 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 FOR 18 * 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: src/sys/i386/i386/busdma_machdep.c,v 1.94 2008/08/15 20:51:31 kmacy Exp $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/malloc.h> 32 #include <sys/mbuf.h> 33 #include <sys/uio.h> 34 #include <sys/bus_dma.h> 35 #include <sys/kernel.h> 36 #include <sys/sysctl.h> 37 #include <sys/lock.h> 38 39 #include <sys/spinlock2.h> 40 41 #include <vm/vm.h> 42 #include <vm/vm_page.h> 43 44 /* XXX needed for to access pmap to convert per-proc virtual to physical */ 45 #include <sys/proc.h> 46 #include <vm/vm_map.h> 47 48 #include <machine/md_var.h> 49 #include <machine/pmap.h> 50 51 #include <bus/cam/cam.h> 52 #include <bus/cam/cam_ccb.h> 53 54 #define MAX_BPAGES 1024 55 56 /* 57 * 16 x N declared on stack. 58 */ 59 #define BUS_DMA_CACHE_SEGMENTS 8 60 61 struct bounce_zone; 62 struct bus_dmamap; 63 64 struct bus_dma_tag { 65 bus_dma_tag_t parent; 66 bus_size_t alignment; 67 bus_size_t boundary; 68 bus_addr_t lowaddr; 69 bus_addr_t highaddr; 70 bus_dma_filter_t *filter; 71 void *filterarg; 72 bus_size_t maxsize; 73 u_int nsegments; 74 bus_size_t maxsegsz; 75 int flags; 76 int ref_count; 77 int map_count; 78 bus_dma_segment_t *segments; 79 struct bounce_zone *bounce_zone; 80 struct spinlock spin; 81 }; 82 83 /* 84 * bus_dma_tag private flags 85 */ 86 #define BUS_DMA_BOUNCE_ALIGN BUS_DMA_BUS2 87 #define BUS_DMA_BOUNCE_LOWADDR BUS_DMA_BUS3 88 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 89 90 #define BUS_DMA_COULD_BOUNCE (BUS_DMA_BOUNCE_LOWADDR | BUS_DMA_BOUNCE_ALIGN) 91 92 #define BUS_DMAMEM_KMALLOC(dmat) \ 93 ((dmat)->maxsize <= PAGE_SIZE && \ 94 (dmat)->alignment <= PAGE_SIZE && \ 95 (dmat)->lowaddr >= ptoa(Maxmem)) 96 97 struct bounce_page { 98 vm_offset_t vaddr; /* kva of bounce buffer */ 99 bus_addr_t busaddr; /* Physical address */ 100 vm_offset_t datavaddr; /* kva of client data */ 101 bus_size_t datacount; /* client data count */ 102 STAILQ_ENTRY(bounce_page) links; 103 }; 104 105 struct bounce_zone { 106 STAILQ_ENTRY(bounce_zone) links; 107 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 108 STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 109 struct spinlock spin; 110 int total_bpages; 111 int free_bpages; 112 int reserved_bpages; 113 int active_bpages; 114 int total_bounced; 115 int total_deferred; 116 int reserve_failed; 117 bus_size_t alignment; 118 bus_addr_t lowaddr; 119 char zoneid[8]; 120 char lowaddrid[20]; 121 struct sysctl_ctx_list sysctl_ctx; 122 struct sysctl_oid *sysctl_tree; 123 }; 124 125 #define BZ_LOCK(bz) spin_lock(&(bz)->spin) 126 #define BZ_UNLOCK(bz) spin_unlock(&(bz)->spin) 127 128 static struct lwkt_token bounce_zone_tok = 129 LWKT_TOKEN_INITIALIZER(bounce_zone_token); 130 static int busdma_zonecount; 131 static STAILQ_HEAD(, bounce_zone) bounce_zone_list = 132 STAILQ_HEAD_INITIALIZER(bounce_zone_list); 133 134 static int busdma_priv_zonecount = -1; 135 136 int busdma_swi_pending; 137 static int total_bounce_pages; 138 static int max_bounce_pages = MAX_BPAGES; 139 static int bounce_alignment = 1; /* XXX temporary */ 140 141 TUNABLE_INT("hw.busdma.max_bpages", &max_bounce_pages); 142 TUNABLE_INT("hw.busdma.bounce_alignment", &bounce_alignment); 143 144 struct bus_dmamap { 145 struct bp_list bpages; 146 int pagesneeded; 147 int pagesreserved; 148 bus_dma_tag_t dmat; 149 void *buf; /* unmapped buffer pointer */ 150 bus_size_t buflen; /* unmapped buffer length */ 151 bus_dmamap_callback_t *callback; 152 void *callback_arg; 153 STAILQ_ENTRY(bus_dmamap) links; 154 }; 155 156 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist = 157 STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist); 158 static struct spinlock bounce_map_list_spin = 159 SPINLOCK_INITIALIZER(&bounce_map_list_spin, "bounce_map_list_spin"); 160 161 static struct bus_dmamap nobounce_dmamap; 162 163 static int alloc_bounce_zone(bus_dma_tag_t); 164 static int alloc_bounce_pages(bus_dma_tag_t, u_int, int); 165 static void free_bounce_pages_all(bus_dma_tag_t); 166 static void free_bounce_zone(bus_dma_tag_t); 167 static int reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int); 168 static void return_bounce_pages(bus_dma_tag_t, bus_dmamap_t); 169 static bus_addr_t add_bounce_page(bus_dma_tag_t, bus_dmamap_t, 170 vm_offset_t, bus_size_t *); 171 static void free_bounce_page(bus_dma_tag_t, struct bounce_page *); 172 173 static bus_dmamap_t get_map_waiting(bus_dma_tag_t); 174 static void add_map_callback(bus_dmamap_t); 175 176 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 177 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages, 178 0, "Total bounce pages"); 179 SYSCTL_INT(_hw_busdma, OID_AUTO, max_bpages, CTLFLAG_RD, &max_bounce_pages, 180 0, "Max bounce pages per bounce zone"); 181 SYSCTL_INT(_hw_busdma, OID_AUTO, bounce_alignment, CTLFLAG_RD, 182 &bounce_alignment, 0, "Obey alignment constraint"); 183 184 static __inline int 185 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 186 { 187 int retval; 188 189 retval = 0; 190 do { 191 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) || 192 (bounce_alignment && (paddr & (dmat->alignment - 1)) != 0)) 193 && (dmat->filter == NULL || 194 dmat->filter(dmat->filterarg, paddr) != 0)) 195 retval = 1; 196 197 dmat = dmat->parent; 198 } while (retval == 0 && dmat != NULL); 199 return (retval); 200 } 201 202 static __inline 203 bus_dma_segment_t * 204 bus_dma_tag_lock(bus_dma_tag_t tag, bus_dma_segment_t *cache) 205 { 206 if (tag->flags & BUS_DMA_PROTECTED) 207 return(tag->segments); 208 209 if (tag->nsegments <= BUS_DMA_CACHE_SEGMENTS) 210 return(cache); 211 spin_lock(&tag->spin); 212 return(tag->segments); 213 } 214 215 static __inline 216 void 217 bus_dma_tag_unlock(bus_dma_tag_t tag) 218 { 219 if (tag->flags & BUS_DMA_PROTECTED) 220 return; 221 222 if (tag->nsegments > BUS_DMA_CACHE_SEGMENTS) 223 spin_unlock(&tag->spin); 224 } 225 226 /* 227 * Allocate a device specific dma_tag. 228 */ 229 int 230 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 231 bus_size_t boundary, bus_addr_t lowaddr, 232 bus_addr_t highaddr, bus_dma_filter_t *filter, 233 void *filterarg, bus_size_t maxsize, int nsegments, 234 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat) 235 { 236 bus_dma_tag_t newtag; 237 int error = 0; 238 239 /* 240 * Sanity checks 241 */ 242 243 if (alignment == 0) 244 alignment = 1; 245 if (alignment & (alignment - 1)) 246 panic("alignment must be power of 2"); 247 248 if (boundary != 0) { 249 if (boundary & (boundary - 1)) 250 panic("boundary must be power of 2"); 251 if (boundary < maxsegsz) { 252 kprintf("boundary < maxsegsz:\n"); 253 print_backtrace(-1); 254 maxsegsz = boundary; 255 } 256 } 257 258 /* Return a NULL tag on failure */ 259 *dmat = NULL; 260 261 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT | M_ZERO); 262 263 spin_init(&newtag->spin, "busdmacreate"); 264 newtag->parent = parent; 265 newtag->alignment = alignment; 266 newtag->boundary = boundary; 267 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 268 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 269 newtag->filter = filter; 270 newtag->filterarg = filterarg; 271 newtag->maxsize = maxsize; 272 newtag->nsegments = nsegments; 273 newtag->maxsegsz = maxsegsz; 274 newtag->flags = flags; 275 newtag->ref_count = 1; /* Count ourself */ 276 newtag->map_count = 0; 277 newtag->segments = NULL; 278 newtag->bounce_zone = NULL; 279 280 /* Take into account any restrictions imposed by our parent tag */ 281 if (parent != NULL) { 282 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 283 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 284 285 if (newtag->boundary == 0) { 286 newtag->boundary = parent->boundary; 287 } else if (parent->boundary != 0) { 288 newtag->boundary = MIN(parent->boundary, 289 newtag->boundary); 290 } 291 292 #ifdef notyet 293 newtag->alignment = MAX(parent->alignment, newtag->alignment); 294 #endif 295 296 if (newtag->filter == NULL) { 297 /* 298 * Short circuit looking at our parent directly 299 * since we have encapsulated all of its information 300 */ 301 newtag->filter = parent->filter; 302 newtag->filterarg = parent->filterarg; 303 newtag->parent = parent->parent; 304 } 305 if (newtag->parent != NULL) 306 parent->ref_count++; 307 } 308 309 if (newtag->lowaddr < ptoa(Maxmem)) 310 newtag->flags |= BUS_DMA_BOUNCE_LOWADDR; 311 if (bounce_alignment && newtag->alignment > 1 && 312 !(newtag->flags & BUS_DMA_ALIGNED)) 313 newtag->flags |= BUS_DMA_BOUNCE_ALIGN; 314 315 if ((newtag->flags & BUS_DMA_COULD_BOUNCE) && 316 (flags & BUS_DMA_ALLOCNOW) != 0) { 317 struct bounce_zone *bz; 318 319 /* Must bounce */ 320 321 error = alloc_bounce_zone(newtag); 322 if (error) 323 goto back; 324 bz = newtag->bounce_zone; 325 326 if ((newtag->flags & BUS_DMA_ALLOCALL) == 0 && 327 ptoa(bz->total_bpages) < maxsize) { 328 int pages; 329 330 if (flags & BUS_DMA_ONEBPAGE) { 331 pages = 1; 332 } else { 333 pages = atop(round_page(maxsize)) - 334 bz->total_bpages; 335 pages = MAX(pages, 1); 336 } 337 338 /* Add pages to our bounce pool */ 339 if (alloc_bounce_pages(newtag, pages, flags) < pages) 340 error = ENOMEM; 341 342 /* Performed initial allocation */ 343 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 344 } 345 } 346 back: 347 if (error) { 348 free_bounce_zone(newtag); 349 kfree(newtag, M_DEVBUF); 350 } else { 351 *dmat = newtag; 352 } 353 return error; 354 } 355 356 int 357 bus_dma_tag_destroy(bus_dma_tag_t dmat) 358 { 359 if (dmat != NULL) { 360 if (dmat->map_count != 0) 361 return (EBUSY); 362 363 while (dmat != NULL) { 364 bus_dma_tag_t parent; 365 366 parent = dmat->parent; 367 dmat->ref_count--; 368 if (dmat->ref_count == 0) { 369 free_bounce_zone(dmat); 370 if (dmat->segments != NULL) 371 kfree(dmat->segments, M_DEVBUF); 372 kfree(dmat, M_DEVBUF); 373 /* 374 * Last reference count, so 375 * release our reference 376 * count on our parent. 377 */ 378 dmat = parent; 379 } else 380 dmat = NULL; 381 } 382 } 383 return (0); 384 } 385 386 bus_size_t 387 bus_dma_tag_getmaxsize(bus_dma_tag_t tag) 388 { 389 return(tag->maxsize); 390 } 391 392 /* 393 * Allocate a handle for mapping from kva/uva/physical 394 * address space into bus device space. 395 */ 396 int 397 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 398 { 399 int error; 400 401 error = 0; 402 403 if (dmat->segments == NULL) { 404 KKASSERT(dmat->nsegments && dmat->nsegments < 16384); 405 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) * 406 dmat->nsegments, M_DEVBUF, M_INTWAIT); 407 } 408 409 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 410 struct bounce_zone *bz; 411 int maxpages; 412 413 /* Must bounce */ 414 415 if (dmat->bounce_zone == NULL) { 416 error = alloc_bounce_zone(dmat); 417 if (error) 418 return error; 419 } 420 bz = dmat->bounce_zone; 421 422 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO); 423 424 /* Initialize the new map */ 425 STAILQ_INIT(&((*mapp)->bpages)); 426 427 /* 428 * Attempt to add pages to our pool on a per-instance 429 * basis up to a sane limit. 430 */ 431 if (dmat->flags & BUS_DMA_ALLOCALL) { 432 maxpages = Maxmem - atop(dmat->lowaddr); 433 } else if (dmat->flags & BUS_DMA_BOUNCE_ALIGN) { 434 maxpages = max_bounce_pages; 435 } else { 436 maxpages = MIN(max_bounce_pages, 437 Maxmem - atop(dmat->lowaddr)); 438 } 439 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 || 440 (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 441 int pages; 442 443 if (flags & BUS_DMA_ONEBPAGE) { 444 pages = 1; 445 } else { 446 pages = atop(round_page(dmat->maxsize)); 447 pages = MIN(maxpages - bz->total_bpages, pages); 448 pages = MAX(pages, 1); 449 } 450 if (alloc_bounce_pages(dmat, pages, flags) < pages) 451 error = ENOMEM; 452 453 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 454 if (!error && 455 (dmat->flags & BUS_DMA_ALLOCALL) == 0) 456 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 457 } else { 458 error = 0; 459 } 460 } 461 } else { 462 *mapp = NULL; 463 } 464 if (!error) { 465 dmat->map_count++; 466 } else { 467 kfree(*mapp, M_DEVBUF); 468 *mapp = NULL; 469 } 470 return error; 471 } 472 473 /* 474 * Destroy a handle for mapping from kva/uva/physical 475 * address space into bus device space. 476 */ 477 int 478 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 479 { 480 if (map != NULL && map != (void *)-1) { 481 if (STAILQ_FIRST(&map->bpages) != NULL) 482 return (EBUSY); 483 kfree(map, M_DEVBUF); 484 } 485 dmat->map_count--; 486 return (0); 487 } 488 489 static __inline bus_size_t 490 check_kmalloc(bus_dma_tag_t dmat, const void *vaddr0, int verify) 491 { 492 bus_size_t maxsize = 0; 493 uintptr_t vaddr = (uintptr_t)vaddr0; 494 495 if ((vaddr ^ (vaddr + dmat->maxsize - 1)) & ~PAGE_MASK) { 496 if (verify) 497 panic("boundary check failed\n"); 498 maxsize = dmat->maxsize; 499 } 500 if (vaddr & (dmat->alignment - 1)) { 501 if (verify) 502 panic("alignment check failed\n"); 503 if (dmat->maxsize < dmat->alignment) 504 maxsize = dmat->alignment; 505 else 506 maxsize = dmat->maxsize; 507 } 508 return maxsize; 509 } 510 511 /* 512 * Allocate a piece of memory that can be efficiently mapped into 513 * bus device space based on the constraints lited in the dma tag. 514 * 515 * Use *mapp to record whether we were able to use kmalloc() 516 * or whether we had to use contigmalloc(). 517 */ 518 int 519 bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags, 520 bus_dmamap_t *mapp) 521 { 522 vm_memattr_t attr; 523 int mflags; 524 525 /* If we succeed, no mapping/bouncing will be required */ 526 *mapp = NULL; 527 528 if (dmat->segments == NULL) { 529 KKASSERT(dmat->nsegments < 16384); 530 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) * 531 dmat->nsegments, M_DEVBUF, M_INTWAIT); 532 } 533 534 if (flags & BUS_DMA_NOWAIT) 535 mflags = M_NOWAIT; 536 else 537 mflags = M_WAITOK; 538 if (flags & BUS_DMA_ZERO) 539 mflags |= M_ZERO; 540 if (flags & BUS_DMA_NOCACHE) 541 attr = VM_MEMATTR_UNCACHEABLE; 542 else 543 attr = VM_MEMATTR_DEFAULT; 544 545 /* XXX must alloc with correct mem attribute here */ 546 if (BUS_DMAMEM_KMALLOC(dmat) && attr == VM_MEMATTR_DEFAULT) { 547 bus_size_t maxsize; 548 549 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags); 550 551 /* 552 * XXX 553 * Check whether the allocation 554 * - crossed a page boundary 555 * - was not aligned 556 * Retry with power-of-2 alignment in the above cases. 557 */ 558 maxsize = check_kmalloc(dmat, *vaddr, 0); 559 if (maxsize) { 560 kfree(*vaddr, M_DEVBUF); 561 *vaddr = kmalloc(maxsize, M_DEVBUF, 562 mflags | M_POWEROF2); 563 check_kmalloc(dmat, *vaddr, 1); 564 } 565 } else { 566 /* 567 * XXX Use Contigmalloc until it is merged into this facility 568 * and handles multi-seg allocations. Nobody is doing 569 * multi-seg allocations yet though. 570 */ 571 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 572 0ul, dmat->lowaddr, 573 dmat->alignment, dmat->boundary); 574 *mapp = (void *)-1; 575 } 576 if (*vaddr == NULL) 577 return (ENOMEM); 578 579 if (attr != VM_MEMATTR_DEFAULT) { 580 pmap_change_attr((vm_offset_t)(*vaddr), 581 dmat->maxsize / PAGE_SIZE, attr); 582 } 583 return (0); 584 } 585 586 /* 587 * Free a piece of memory and it's allociated dmamap, that was allocated 588 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 589 */ 590 void 591 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 592 { 593 /* 594 * dmamem does not need to be bounced, so the map should be 595 * NULL 596 */ 597 if (map != NULL && map != (void *)-1) 598 panic("bus_dmamem_free: Invalid map freed"); 599 if (map == NULL) 600 kfree(vaddr, M_DEVBUF); 601 else 602 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 603 } 604 605 static __inline vm_paddr_t 606 _bus_dma_extract(pmap_t pmap, vm_offset_t vaddr) 607 { 608 if (pmap) 609 return pmap_extract(pmap, vaddr, NULL); 610 else 611 return pmap_kextract(vaddr); 612 } 613 614 /* 615 * Utility function to load a linear buffer. lastaddrp holds state 616 * between invocations (for multiple-buffer loads). segp contains 617 * the segment following the starting one on entrace, and the ending 618 * segment on exit. first indicates if this is the first invocation 619 * of this function. 620 */ 621 static int 622 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 623 bus_dmamap_t map, 624 void *buf, bus_size_t buflen, 625 bus_dma_segment_t *segments, 626 int nsegments, 627 pmap_t pmap, 628 int flags, 629 vm_paddr_t *lastpaddrp, 630 int *segp, 631 int first) 632 { 633 vm_offset_t vaddr; 634 vm_paddr_t paddr, nextpaddr; 635 bus_dma_segment_t *sg; 636 bus_addr_t bmask; 637 int seg, error = 0; 638 639 if (map == NULL || map == (void *)-1) 640 map = &nobounce_dmamap; 641 642 #ifdef INVARIANTS 643 if (dmat->flags & BUS_DMA_ALIGNED) 644 KKASSERT(((uintptr_t)buf & (dmat->alignment - 1)) == 0); 645 #endif 646 647 /* 648 * If we are being called during a callback, pagesneeded will 649 * be non-zero, so we can avoid doing the work twice. 650 */ 651 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) && 652 map != &nobounce_dmamap && map->pagesneeded == 0) { 653 vm_offset_t vendaddr; 654 655 /* 656 * Count the number of bounce pages 657 * needed in order to complete this transfer 658 */ 659 vaddr = (vm_offset_t)buf; 660 vendaddr = (vm_offset_t)buf + buflen; 661 662 while (vaddr < vendaddr) { 663 paddr = _bus_dma_extract(pmap, vaddr); 664 if (run_filter(dmat, paddr) != 0) 665 map->pagesneeded++; 666 vaddr += (PAGE_SIZE - (vaddr & PAGE_MASK)); 667 } 668 } 669 670 /* Reserve Necessary Bounce Pages */ 671 if (map->pagesneeded != 0) { 672 struct bounce_zone *bz; 673 674 bz = dmat->bounce_zone; 675 BZ_LOCK(bz); 676 if (flags & BUS_DMA_NOWAIT) { 677 if (reserve_bounce_pages(dmat, map, 0) != 0) { 678 BZ_UNLOCK(bz); 679 error = ENOMEM; 680 goto free_bounce; 681 } 682 } else { 683 if (reserve_bounce_pages(dmat, map, 1) != 0) { 684 /* Queue us for resources */ 685 map->dmat = dmat; 686 map->buf = buf; 687 map->buflen = buflen; 688 689 STAILQ_INSERT_TAIL( 690 &dmat->bounce_zone->bounce_map_waitinglist, 691 map, links); 692 BZ_UNLOCK(bz); 693 694 return (EINPROGRESS); 695 } 696 } 697 BZ_UNLOCK(bz); 698 } 699 700 KKASSERT(*segp >= 1 && *segp <= nsegments); 701 seg = *segp; 702 sg = &segments[seg - 1]; 703 704 vaddr = (vm_offset_t)buf; 705 nextpaddr = *lastpaddrp; 706 bmask = ~(dmat->boundary - 1); /* note: will be 0 if boundary is 0 */ 707 708 /* force at least one segment */ 709 do { 710 bus_size_t size; 711 712 /* 713 * Per-page main loop 714 */ 715 paddr = _bus_dma_extract(pmap, vaddr); 716 size = PAGE_SIZE - (paddr & PAGE_MASK); 717 if (size > buflen) 718 size = buflen; 719 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) { 720 /* 721 * NOTE: paddr may have different in-page offset, 722 * unless BUS_DMA_KEEP_PG_OFFSET is set. 723 */ 724 paddr = add_bounce_page(dmat, map, vaddr, &size); 725 } 726 727 /* 728 * Fill in the bus_dma_segment 729 */ 730 if (first) { 731 sg->ds_addr = paddr; 732 sg->ds_len = size; 733 first = 0; 734 } else if (paddr == nextpaddr) { 735 sg->ds_len += size; 736 } else { 737 sg++; 738 seg++; 739 if (seg > nsegments) 740 break; 741 sg->ds_addr = paddr; 742 sg->ds_len = size; 743 } 744 nextpaddr = paddr + size; 745 746 /* 747 * Handle maxsegsz and boundary issues with a nested loop 748 */ 749 for (;;) { 750 bus_size_t tmpsize; 751 752 /* 753 * Limit to the boundary and maximum segment size 754 */ 755 if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) { 756 tmpsize = dmat->boundary - 757 (sg->ds_addr & ~bmask); 758 if (tmpsize > dmat->maxsegsz) 759 tmpsize = dmat->maxsegsz; 760 KKASSERT(tmpsize < sg->ds_len); 761 } else if (sg->ds_len > dmat->maxsegsz) { 762 tmpsize = dmat->maxsegsz; 763 } else { 764 break; 765 } 766 767 /* 768 * Futz, split the data into a new segment. 769 */ 770 if (seg >= nsegments) 771 goto fail; 772 sg[1].ds_len = sg[0].ds_len - tmpsize; 773 sg[1].ds_addr = sg[0].ds_addr + tmpsize; 774 sg[0].ds_len = tmpsize; 775 sg++; 776 seg++; 777 } 778 779 /* 780 * Adjust for loop 781 */ 782 buflen -= size; 783 vaddr += size; 784 } while (buflen > 0); 785 fail: 786 if (buflen != 0) 787 error = EFBIG; 788 789 *segp = seg; 790 *lastpaddrp = nextpaddr; 791 792 free_bounce: 793 if (error && (dmat->flags & BUS_DMA_COULD_BOUNCE) && 794 map != &nobounce_dmamap) { 795 _bus_dmamap_unload(dmat, map); 796 return_bounce_pages(dmat, map); 797 } 798 return error; 799 } 800 801 /* 802 * Map the buffer buf into bus space using the dmamap map. 803 */ 804 int 805 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 806 bus_size_t buflen, bus_dmamap_callback_t *callback, 807 void *callback_arg, int flags) 808 { 809 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS]; 810 bus_dma_segment_t *segments; 811 vm_paddr_t lastaddr = 0; 812 int error, nsegs = 1; 813 814 if (map != NULL && map != (void *)-1) { 815 /* 816 * XXX 817 * Follow old semantics. Once all of the callers are fixed, 818 * we should get rid of these internal flag "adjustment". 819 */ 820 flags &= ~BUS_DMA_NOWAIT; 821 flags |= BUS_DMA_WAITOK; 822 823 map->callback = callback; 824 map->callback_arg = callback_arg; 825 } 826 827 segments = bus_dma_tag_lock(dmat, cache_segments); 828 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, 829 segments, dmat->nsegments, 830 NULL, flags, &lastaddr, &nsegs, 1); 831 if (error == EINPROGRESS) { 832 KKASSERT((dmat->flags & 833 (BUS_DMA_PRIVBZONE | BUS_DMA_ALLOCALL)) != 834 (BUS_DMA_PRIVBZONE | BUS_DMA_ALLOCALL)); 835 836 if (dmat->flags & BUS_DMA_PROTECTED) 837 panic("protected dmamap callback will be defered"); 838 839 bus_dma_tag_unlock(dmat); 840 return error; 841 } 842 callback(callback_arg, segments, nsegs, error); 843 bus_dma_tag_unlock(dmat); 844 return 0; 845 } 846 847 /* 848 * Like _bus_dmamap_load(), but for ccb. 849 */ 850 int 851 bus_dmamap_load_ccb(bus_dma_tag_t dmat, bus_dmamap_t map, union ccb *ccb, 852 bus_dmamap_callback_t *callback, void *callback_arg, int flags) 853 { 854 const struct ccb_scsiio *csio; 855 856 KASSERT(ccb->ccb_h.func_code == XPT_SCSI_IO || 857 ccb->ccb_h.func_code == XPT_CONT_TARGET_IO, 858 ("invalid ccb func_code %u", ccb->ccb_h.func_code)); 859 csio = &ccb->csio; 860 861 return (bus_dmamap_load(dmat, map, csio->data_ptr, csio->dxfer_len, 862 callback, callback_arg, flags)); 863 } 864 865 /* 866 * Like _bus_dmamap_load(), but for mbufs. 867 */ 868 int 869 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 870 struct mbuf *m0, 871 bus_dmamap_callback2_t *callback, void *callback_arg, 872 int flags) 873 { 874 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS]; 875 bus_dma_segment_t *segments; 876 int nsegs, error; 877 878 /* 879 * XXX 880 * Follow old semantics. Once all of the callers are fixed, 881 * we should get rid of these internal flag "adjustment". 882 */ 883 flags &= ~BUS_DMA_WAITOK; 884 flags |= BUS_DMA_NOWAIT; 885 886 segments = bus_dma_tag_lock(dmat, cache_segments); 887 error = bus_dmamap_load_mbuf_segment(dmat, map, m0, 888 segments, dmat->nsegments, &nsegs, flags); 889 if (error) { 890 /* force "no valid mappings" in callback */ 891 callback(callback_arg, segments, 0, 892 0, error); 893 } else { 894 callback(callback_arg, segments, nsegs, 895 m0->m_pkthdr.len, error); 896 } 897 bus_dma_tag_unlock(dmat); 898 return error; 899 } 900 901 int 902 bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat, bus_dmamap_t map, 903 struct mbuf *m0, 904 bus_dma_segment_t *segs, int maxsegs, 905 int *nsegs, int flags) 906 { 907 int error; 908 909 M_ASSERTPKTHDR(m0); 910 911 KASSERT(maxsegs >= 1, ("invalid maxsegs %d", maxsegs)); 912 KASSERT(maxsegs <= dmat->nsegments, 913 ("%d too many segments, dmat only supports %d segments", 914 maxsegs, dmat->nsegments)); 915 KASSERT(flags & BUS_DMA_NOWAIT, 916 ("only BUS_DMA_NOWAIT is supported")); 917 918 if (m0->m_pkthdr.len <= dmat->maxsize) { 919 int first = 1; 920 vm_paddr_t lastaddr = 0; 921 struct mbuf *m; 922 923 *nsegs = 1; 924 error = 0; 925 for (m = m0; m != NULL && error == 0; m = m->m_next) { 926 if (m->m_len == 0) 927 continue; 928 929 error = _bus_dmamap_load_buffer(dmat, map, 930 m->m_data, m->m_len, 931 segs, maxsegs, 932 NULL, flags, &lastaddr, 933 nsegs, first); 934 if (error == ENOMEM && !first) { 935 /* 936 * Out of bounce pages due to too many 937 * fragments in the mbuf chain; return 938 * EFBIG instead. 939 */ 940 error = EFBIG; 941 break; 942 } 943 first = 0; 944 } 945 #ifdef INVARIANTS 946 if (!error) 947 KKASSERT(*nsegs <= maxsegs && *nsegs >= 1); 948 #endif 949 } else { 950 *nsegs = 0; 951 error = EINVAL; 952 } 953 KKASSERT(error != EINPROGRESS); 954 return error; 955 } 956 957 /* 958 * Like _bus_dmamap_load(), but for uios. 959 */ 960 int 961 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 962 struct uio *uio, 963 bus_dmamap_callback2_t *callback, void *callback_arg, 964 int flags) 965 { 966 vm_paddr_t lastaddr; 967 int nsegs, error, first, i; 968 bus_size_t resid; 969 struct iovec *iov; 970 pmap_t pmap; 971 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS]; 972 bus_dma_segment_t *segments; 973 bus_dma_segment_t *segs; 974 int nsegs_left; 975 976 if (dmat->nsegments <= BUS_DMA_CACHE_SEGMENTS) 977 segments = cache_segments; 978 else 979 segments = kmalloc(sizeof(bus_dma_segment_t) * dmat->nsegments, 980 M_DEVBUF, M_WAITOK | M_ZERO); 981 982 /* 983 * XXX 984 * Follow old semantics. Once all of the callers are fixed, 985 * we should get rid of these internal flag "adjustment". 986 */ 987 flags &= ~BUS_DMA_WAITOK; 988 flags |= BUS_DMA_NOWAIT; 989 990 resid = (bus_size_t)uio->uio_resid; 991 iov = uio->uio_iov; 992 993 segs = segments; 994 nsegs_left = dmat->nsegments; 995 996 if (uio->uio_segflg == UIO_USERSPACE) { 997 struct thread *td; 998 999 td = uio->uio_td; 1000 KASSERT(td != NULL && td->td_proc != NULL, 1001 ("bus_dmamap_load_uio: USERSPACE but no proc")); 1002 pmap = vmspace_pmap(td->td_proc->p_vmspace); 1003 } else { 1004 pmap = NULL; 1005 } 1006 1007 error = 0; 1008 nsegs = 1; 1009 first = 1; 1010 lastaddr = 0; 1011 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 1012 /* 1013 * Now at the first iovec to load. Load each iovec 1014 * until we have exhausted the residual count. 1015 */ 1016 bus_size_t minlen = 1017 resid < iov[i].iov_len ? resid : iov[i].iov_len; 1018 caddr_t addr = (caddr_t) iov[i].iov_base; 1019 1020 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen, 1021 segs, nsegs_left, 1022 pmap, flags, &lastaddr, &nsegs, first); 1023 first = 0; 1024 1025 resid -= minlen; 1026 if (error == 0) { 1027 nsegs_left -= nsegs; 1028 segs += nsegs; 1029 } 1030 } 1031 1032 /* 1033 * Minimum one DMA segment, even if 0-length buffer. 1034 */ 1035 if (nsegs_left == dmat->nsegments) 1036 --nsegs_left; 1037 1038 if (error) { 1039 /* force "no valid mappings" in callback */ 1040 callback(callback_arg, segments, 0, 1041 0, error); 1042 } else { 1043 callback(callback_arg, segments, dmat->nsegments - nsegs_left, 1044 (bus_size_t)uio->uio_resid, error); 1045 } 1046 if (dmat->nsegments > BUS_DMA_CACHE_SEGMENTS) 1047 kfree(segments, M_DEVBUF); 1048 return error; 1049 } 1050 1051 /* 1052 * Release the mapping held by map. 1053 */ 1054 void 1055 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 1056 { 1057 struct bounce_page *bpage; 1058 1059 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 1060 STAILQ_REMOVE_HEAD(&map->bpages, links); 1061 free_bounce_page(dmat, bpage); 1062 } 1063 } 1064 1065 void 1066 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 1067 { 1068 struct bounce_page *bpage; 1069 1070 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 1071 /* 1072 * Handle data bouncing. We might also 1073 * want to add support for invalidating 1074 * the caches on broken hardware 1075 */ 1076 if (op & BUS_DMASYNC_PREWRITE) { 1077 while (bpage != NULL) { 1078 bcopy((void *)bpage->datavaddr, 1079 (void *)bpage->vaddr, 1080 bpage->datacount); 1081 bpage = STAILQ_NEXT(bpage, links); 1082 } 1083 cpu_sfence(); 1084 dmat->bounce_zone->total_bounced++; 1085 } 1086 if (op & BUS_DMASYNC_POSTREAD) { 1087 cpu_lfence(); 1088 while (bpage != NULL) { 1089 bcopy((void *)bpage->vaddr, 1090 (void *)bpage->datavaddr, 1091 bpage->datacount); 1092 bpage = STAILQ_NEXT(bpage, links); 1093 } 1094 dmat->bounce_zone->total_bounced++; 1095 } 1096 /* BUS_DMASYNC_PREREAD - no operation on intel */ 1097 /* BUS_DMASYNC_POSTWRITE - no operation on intel */ 1098 } 1099 } 1100 1101 static int 1102 alloc_bounce_zone(bus_dma_tag_t dmat) 1103 { 1104 struct bounce_zone *bz, *new_bz; 1105 1106 KASSERT(dmat->bounce_zone == NULL, 1107 ("bounce zone was already assigned")); 1108 1109 new_bz = kmalloc(sizeof(*new_bz), M_DEVBUF, M_INTWAIT | M_ZERO); 1110 1111 lwkt_gettoken(&bounce_zone_tok); 1112 1113 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) { 1114 /* 1115 * For shared bounce zone, check to see 1116 * if we already have a suitable zone 1117 */ 1118 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1119 if (dmat->alignment <= bz->alignment && 1120 dmat->lowaddr >= bz->lowaddr) { 1121 lwkt_reltoken(&bounce_zone_tok); 1122 1123 dmat->bounce_zone = bz; 1124 kfree(new_bz, M_DEVBUF); 1125 return 0; 1126 } 1127 } 1128 } 1129 bz = new_bz; 1130 1131 spin_init(&bz->spin, "allocbouncezone"); 1132 STAILQ_INIT(&bz->bounce_page_list); 1133 STAILQ_INIT(&bz->bounce_map_waitinglist); 1134 bz->free_bpages = 0; 1135 bz->reserved_bpages = 0; 1136 bz->active_bpages = 0; 1137 bz->lowaddr = dmat->lowaddr; 1138 bz->alignment = round_page(dmat->alignment); 1139 ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1140 1141 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) { 1142 ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1143 busdma_zonecount++; 1144 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1145 } else { 1146 ksnprintf(bz->zoneid, 8, "zone%d", busdma_priv_zonecount); 1147 busdma_priv_zonecount--; 1148 } 1149 1150 lwkt_reltoken(&bounce_zone_tok); 1151 1152 dmat->bounce_zone = bz; 1153 1154 sysctl_ctx_init(&bz->sysctl_ctx); 1155 bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx, 1156 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1157 CTLFLAG_RD, 0, ""); 1158 if (bz->sysctl_tree == NULL) { 1159 sysctl_ctx_free(&bz->sysctl_ctx); 1160 return 0; /* XXX error code? */ 1161 } 1162 1163 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1164 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1165 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1166 "Total bounce pages"); 1167 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1168 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1169 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1170 "Free bounce pages"); 1171 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1172 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1173 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1174 "Reserved bounce pages"); 1175 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1176 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1177 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1178 "Active bounce pages"); 1179 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1180 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1181 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1182 "Total bounce requests"); 1183 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1184 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1185 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1186 "Total bounce requests that were deferred"); 1187 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1188 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1189 "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0, 1190 "Total bounce page reservations that were failed"); 1191 SYSCTL_ADD_STRING(&bz->sysctl_ctx, 1192 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1193 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1194 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1195 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1196 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1197 1198 return 0; 1199 } 1200 1201 static int 1202 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages, int flags) 1203 { 1204 struct bounce_zone *bz = dmat->bounce_zone; 1205 int count = 0, mflags; 1206 1207 if (flags & BUS_DMA_NOWAIT) 1208 mflags = M_NOWAIT; 1209 else 1210 mflags = M_WAITOK; 1211 1212 while (numpages > 0) { 1213 struct bounce_page *bpage; 1214 1215 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO); 1216 1217 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1218 mflags, 0ul, 1219 bz->lowaddr, 1220 bz->alignment, 0); 1221 if (bpage->vaddr == 0) { 1222 kfree(bpage, M_DEVBUF); 1223 break; 1224 } 1225 bpage->busaddr = pmap_kextract(bpage->vaddr); 1226 1227 BZ_LOCK(bz); 1228 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1229 total_bounce_pages++; 1230 bz->total_bpages++; 1231 bz->free_bpages++; 1232 BZ_UNLOCK(bz); 1233 1234 count++; 1235 numpages--; 1236 } 1237 return count; 1238 } 1239 1240 static void 1241 free_bounce_pages_all(bus_dma_tag_t dmat) 1242 { 1243 struct bounce_zone *bz = dmat->bounce_zone; 1244 struct bounce_page *bpage; 1245 1246 BZ_LOCK(bz); 1247 1248 while ((bpage = STAILQ_FIRST(&bz->bounce_page_list)) != NULL) { 1249 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1250 1251 KKASSERT(total_bounce_pages > 0); 1252 total_bounce_pages--; 1253 1254 KKASSERT(bz->total_bpages > 0); 1255 bz->total_bpages--; 1256 1257 KKASSERT(bz->free_bpages > 0); 1258 bz->free_bpages--; 1259 1260 BZ_UNLOCK(bz); 1261 contigfree((void *)bpage->vaddr, PAGE_SIZE, M_DEVBUF); 1262 kfree(bpage, M_DEVBUF); 1263 BZ_LOCK(bz); 1264 } 1265 if (bz->total_bpages) { 1266 kprintf("#%d bounce pages are still in use\n", 1267 bz->total_bpages); 1268 print_backtrace(-1); 1269 } 1270 1271 BZ_UNLOCK(bz); 1272 } 1273 1274 static void 1275 free_bounce_zone(bus_dma_tag_t dmat) 1276 { 1277 struct bounce_zone *bz = dmat->bounce_zone; 1278 1279 if (bz == NULL) 1280 return; 1281 1282 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) 1283 return; 1284 1285 free_bounce_pages_all(dmat); 1286 dmat->bounce_zone = NULL; 1287 1288 if (bz->sysctl_tree != NULL) 1289 sysctl_ctx_free(&bz->sysctl_ctx); 1290 kfree(bz, M_DEVBUF); 1291 } 1292 1293 /* Assume caller holds bounce zone spinlock */ 1294 static int 1295 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1296 { 1297 struct bounce_zone *bz = dmat->bounce_zone; 1298 int pages; 1299 1300 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1301 if (!commit && map->pagesneeded > (map->pagesreserved + pages)) { 1302 bz->reserve_failed++; 1303 return (map->pagesneeded - (map->pagesreserved + pages)); 1304 } 1305 1306 bz->free_bpages -= pages; 1307 1308 bz->reserved_bpages += pages; 1309 KKASSERT(bz->reserved_bpages <= bz->total_bpages); 1310 1311 map->pagesreserved += pages; 1312 pages = map->pagesneeded - map->pagesreserved; 1313 1314 return pages; 1315 } 1316 1317 static void 1318 return_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map) 1319 { 1320 struct bounce_zone *bz = dmat->bounce_zone; 1321 int reserved = map->pagesreserved; 1322 bus_dmamap_t wait_map; 1323 1324 map->pagesreserved = 0; 1325 map->pagesneeded = 0; 1326 1327 if (reserved == 0) 1328 return; 1329 1330 BZ_LOCK(bz); 1331 1332 bz->free_bpages += reserved; 1333 KKASSERT(bz->free_bpages <= bz->total_bpages); 1334 1335 KKASSERT(bz->reserved_bpages >= reserved); 1336 bz->reserved_bpages -= reserved; 1337 1338 wait_map = get_map_waiting(dmat); 1339 1340 BZ_UNLOCK(bz); 1341 1342 if (wait_map != NULL) 1343 add_map_callback(map); 1344 } 1345 1346 static bus_addr_t 1347 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1348 bus_size_t *sizep) 1349 { 1350 struct bounce_zone *bz = dmat->bounce_zone; 1351 struct bounce_page *bpage; 1352 bus_size_t size; 1353 1354 KASSERT(map->pagesneeded > 0, ("map doesn't need any pages")); 1355 map->pagesneeded--; 1356 1357 KASSERT(map->pagesreserved > 0, ("map doesn't reserve any pages")); 1358 map->pagesreserved--; 1359 1360 BZ_LOCK(bz); 1361 1362 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1363 KASSERT(bpage != NULL, ("free page list is empty")); 1364 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1365 1366 KKASSERT(bz->reserved_bpages > 0); 1367 bz->reserved_bpages--; 1368 1369 bz->active_bpages++; 1370 KKASSERT(bz->active_bpages <= bz->total_bpages); 1371 1372 BZ_UNLOCK(bz); 1373 1374 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1375 /* 1376 * Page offset needs to be preserved. No size adjustments 1377 * needed. 1378 */ 1379 bpage->vaddr |= vaddr & PAGE_MASK; 1380 bpage->busaddr |= vaddr & PAGE_MASK; 1381 size = *sizep; 1382 } else { 1383 /* 1384 * Realign to bounce page base address, reduce size if 1385 * necessary. Bounce pages are typically already 1386 * page-aligned. 1387 */ 1388 size = PAGE_SIZE - (bpage->busaddr & PAGE_MASK); 1389 if (size < *sizep) { 1390 *sizep = size; 1391 } else { 1392 size = *sizep; 1393 } 1394 } 1395 1396 bpage->datavaddr = vaddr; 1397 bpage->datacount = size; 1398 STAILQ_INSERT_TAIL(&map->bpages, bpage, links); 1399 return bpage->busaddr; 1400 } 1401 1402 static void 1403 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1404 { 1405 struct bounce_zone *bz = dmat->bounce_zone; 1406 bus_dmamap_t map; 1407 1408 bpage->datavaddr = 0; 1409 bpage->datacount = 0; 1410 1411 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1412 /* 1413 * Reset the bounce page to start at offset 0. Other uses 1414 * of this bounce page may need to store a full page of 1415 * data and/or assume it starts on a page boundary. 1416 */ 1417 bpage->vaddr &= ~PAGE_MASK; 1418 bpage->busaddr &= ~PAGE_MASK; 1419 } 1420 1421 BZ_LOCK(bz); 1422 1423 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1424 1425 bz->free_bpages++; 1426 KKASSERT(bz->free_bpages <= bz->total_bpages); 1427 1428 KKASSERT(bz->active_bpages > 0); 1429 bz->active_bpages--; 1430 1431 map = get_map_waiting(dmat); 1432 1433 BZ_UNLOCK(bz); 1434 1435 if (map != NULL && map != (void *)-1) 1436 add_map_callback(map); 1437 } 1438 1439 /* Assume caller holds bounce zone spinlock */ 1440 static bus_dmamap_t 1441 get_map_waiting(bus_dma_tag_t dmat) 1442 { 1443 struct bounce_zone *bz = dmat->bounce_zone; 1444 bus_dmamap_t map; 1445 1446 map = STAILQ_FIRST(&bz->bounce_map_waitinglist); 1447 if (map != NULL && map != (void *)-1) { 1448 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1449 STAILQ_REMOVE_HEAD(&bz->bounce_map_waitinglist, links); 1450 bz->total_deferred++; 1451 } else { 1452 map = NULL; 1453 } 1454 } 1455 return map; 1456 } 1457 1458 static void 1459 add_map_callback(bus_dmamap_t map) 1460 { 1461 spin_lock(&bounce_map_list_spin); 1462 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, map, links); 1463 busdma_swi_pending = 1; 1464 setsoftvm(); 1465 spin_unlock(&bounce_map_list_spin); 1466 } 1467 1468 void 1469 busdma_swi(void) 1470 { 1471 bus_dmamap_t map; 1472 1473 spin_lock(&bounce_map_list_spin); 1474 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1475 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1476 spin_unlock(&bounce_map_list_spin); 1477 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1478 map->callback, map->callback_arg, /*flags*/0); 1479 spin_lock(&bounce_map_list_spin); 1480 } 1481 spin_unlock(&bounce_map_list_spin); 1482 } 1483 1484 int 1485 bus_space_map(bus_space_tag_t t __unused, bus_addr_t addr, bus_size_t size, 1486 int flags __unused, bus_space_handle_t *bshp) 1487 { 1488 1489 if (t == X86_64_BUS_SPACE_MEM) 1490 *bshp = (uintptr_t)pmap_mapdev(addr, size); 1491 else 1492 *bshp = addr; 1493 return (0); 1494 } 1495 1496 void 1497 bus_space_unmap(bus_space_tag_t t, bus_space_handle_t bsh, bus_size_t size) 1498 { 1499 if (t == X86_64_BUS_SPACE_MEM) 1500 pmap_unmapdev(bsh, size); 1501 } 1502