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/thread2.h> 40 #include <sys/spinlock2.h> 41 #include <sys/mplock2.h> 42 43 #include <vm/vm.h> 44 #include <vm/vm_page.h> 45 46 /* XXX needed for to access pmap to convert per-proc virtual to physical */ 47 #include <sys/proc.h> 48 #include <sys/lock.h> 49 #include <vm/vm_map.h> 50 51 #include <machine/md_var.h> 52 53 #define MAX_BPAGES 1024 54 55 /* 56 * 16 x N declared on stack. 57 */ 58 #define BUS_DMA_CACHE_SEGMENTS 8 59 60 struct bounce_zone; 61 struct bus_dmamap; 62 63 struct bus_dma_tag { 64 bus_dma_tag_t parent; 65 bus_size_t alignment; 66 bus_size_t boundary; 67 bus_addr_t lowaddr; 68 bus_addr_t highaddr; 69 bus_dma_filter_t *filter; 70 void *filterarg; 71 bus_size_t maxsize; 72 u_int nsegments; 73 bus_size_t maxsegsz; 74 int flags; 75 int ref_count; 76 int map_count; 77 bus_dma_segment_t *segments; 78 struct bounce_zone *bounce_zone; 79 #ifdef SMP 80 struct spinlock spin; 81 #else 82 int unused0; 83 #endif 84 }; 85 86 /* 87 * bus_dma_tag private flags 88 */ 89 #define BUS_DMA_BOUNCE_ALIGN BUS_DMA_BUS2 90 #define BUS_DMA_BOUNCE_LOWADDR BUS_DMA_BUS3 91 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 92 93 #define BUS_DMA_COULD_BOUNCE (BUS_DMA_BOUNCE_LOWADDR | BUS_DMA_BOUNCE_ALIGN) 94 95 #define BUS_DMAMEM_KMALLOC(dmat) \ 96 ((dmat)->maxsize <= PAGE_SIZE && \ 97 (dmat)->alignment <= PAGE_SIZE && \ 98 (dmat)->lowaddr >= ptoa(Maxmem)) 99 100 struct bounce_page { 101 vm_offset_t vaddr; /* kva of bounce buffer */ 102 bus_addr_t busaddr; /* Physical address */ 103 vm_offset_t datavaddr; /* kva of client data */ 104 bus_size_t datacount; /* client data count */ 105 STAILQ_ENTRY(bounce_page) links; 106 }; 107 108 struct bounce_zone { 109 STAILQ_ENTRY(bounce_zone) links; 110 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 111 STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 112 #ifdef SMP 113 struct spinlock spin; 114 #else 115 int unused0; 116 #endif 117 int total_bpages; 118 int free_bpages; 119 int reserved_bpages; 120 int active_bpages; 121 int total_bounced; 122 int total_deferred; 123 int reserve_failed; 124 bus_size_t alignment; 125 bus_addr_t lowaddr; 126 char zoneid[8]; 127 char lowaddrid[20]; 128 struct sysctl_ctx_list sysctl_ctx; 129 struct sysctl_oid *sysctl_tree; 130 }; 131 132 #ifdef SMP 133 #define BZ_LOCK(bz) spin_lock(&(bz)->spin) 134 #define BZ_UNLOCK(bz) spin_unlock(&(bz)->spin) 135 #else 136 #define BZ_LOCK(bz) crit_enter() 137 #define BZ_UNLOCK(bz) crit_exit() 138 #endif 139 140 static struct lwkt_token bounce_zone_tok = 141 LWKT_TOKEN_INITIALIZER(bounce_zone_token); 142 static int busdma_zonecount; 143 static STAILQ_HEAD(, bounce_zone) bounce_zone_list = 144 STAILQ_HEAD_INITIALIZER(bounce_zone_list); 145 146 static int busdma_priv_zonecount = -1; 147 148 int busdma_swi_pending; 149 static int total_bounce_pages; 150 static int max_bounce_pages = MAX_BPAGES; 151 static int bounce_alignment = 1; /* XXX temporary */ 152 153 TUNABLE_INT("hw.busdma.max_bpages", &max_bounce_pages); 154 TUNABLE_INT("hw.busdma.bounce_alignment", &bounce_alignment); 155 156 struct bus_dmamap { 157 struct bp_list bpages; 158 int pagesneeded; 159 int pagesreserved; 160 bus_dma_tag_t dmat; 161 void *buf; /* unmapped buffer pointer */ 162 bus_size_t buflen; /* unmapped buffer length */ 163 bus_dmamap_callback_t *callback; 164 void *callback_arg; 165 STAILQ_ENTRY(bus_dmamap) links; 166 }; 167 168 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist = 169 STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist); 170 static struct spinlock bounce_map_list_spin = 171 SPINLOCK_INITIALIZER(&bounce_map_list_spin); 172 173 static struct bus_dmamap nobounce_dmamap; 174 175 static int alloc_bounce_zone(bus_dma_tag_t); 176 static int alloc_bounce_pages(bus_dma_tag_t, u_int, int); 177 static void free_bounce_pages_all(bus_dma_tag_t); 178 static void free_bounce_zone(bus_dma_tag_t); 179 static int reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int); 180 static void return_bounce_pages(bus_dma_tag_t, bus_dmamap_t); 181 static bus_addr_t add_bounce_page(bus_dma_tag_t, bus_dmamap_t, 182 vm_offset_t, bus_size_t); 183 static void free_bounce_page(bus_dma_tag_t, struct bounce_page *); 184 185 static bus_dmamap_t get_map_waiting(bus_dma_tag_t); 186 static void add_map_callback(bus_dmamap_t); 187 188 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 189 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages, 190 0, "Total bounce pages"); 191 SYSCTL_INT(_hw_busdma, OID_AUTO, max_bpages, CTLFLAG_RD, &max_bounce_pages, 192 0, "Max bounce pages per bounce zone"); 193 SYSCTL_INT(_hw_busdma, OID_AUTO, bounce_alignment, CTLFLAG_RD, 194 &bounce_alignment, 0, "Obey alignment constraint"); 195 196 static __inline int 197 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 198 { 199 int retval; 200 201 retval = 0; 202 do { 203 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) || 204 (bounce_alignment && (paddr & (dmat->alignment - 1)) != 0)) 205 && (dmat->filter == NULL || 206 dmat->filter(dmat->filterarg, paddr) != 0)) 207 retval = 1; 208 209 dmat = dmat->parent; 210 } while (retval == 0 && dmat != NULL); 211 return (retval); 212 } 213 214 static __inline 215 bus_dma_segment_t * 216 bus_dma_tag_lock(bus_dma_tag_t tag, bus_dma_segment_t *cache) 217 { 218 if (tag->flags & BUS_DMA_PROTECTED) 219 return(tag->segments); 220 221 if (tag->nsegments <= BUS_DMA_CACHE_SEGMENTS) 222 return(cache); 223 #ifdef SMP 224 spin_lock(&tag->spin); 225 #endif 226 return(tag->segments); 227 } 228 229 static __inline 230 void 231 bus_dma_tag_unlock(bus_dma_tag_t tag) 232 { 233 #ifdef SMP 234 if (tag->flags & BUS_DMA_PROTECTED) 235 return; 236 237 if (tag->nsegments > BUS_DMA_CACHE_SEGMENTS) 238 spin_unlock(&tag->spin); 239 #endif 240 } 241 242 /* 243 * Allocate a device specific dma_tag. 244 */ 245 int 246 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 247 bus_size_t boundary, bus_addr_t lowaddr, 248 bus_addr_t highaddr, bus_dma_filter_t *filter, 249 void *filterarg, bus_size_t maxsize, int nsegments, 250 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat) 251 { 252 bus_dma_tag_t newtag; 253 int error = 0; 254 255 /* 256 * Sanity checks 257 */ 258 259 if (alignment == 0) 260 alignment = 1; 261 if (alignment & (alignment - 1)) 262 panic("alignment must be power of 2"); 263 264 if (boundary != 0) { 265 if (boundary & (boundary - 1)) 266 panic("boundary must be power of 2"); 267 if (boundary < maxsegsz) { 268 kprintf("boundary < maxsegsz:\n"); 269 print_backtrace(-1); 270 maxsegsz = boundary; 271 } 272 } 273 274 /* Return a NULL tag on failure */ 275 *dmat = NULL; 276 277 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT | M_ZERO); 278 279 #ifdef SMP 280 spin_init(&newtag->spin); 281 #endif 282 newtag->parent = parent; 283 newtag->alignment = alignment; 284 newtag->boundary = boundary; 285 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 286 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 287 newtag->filter = filter; 288 newtag->filterarg = filterarg; 289 newtag->maxsize = maxsize; 290 newtag->nsegments = nsegments; 291 newtag->maxsegsz = maxsegsz; 292 newtag->flags = flags; 293 newtag->ref_count = 1; /* Count ourself */ 294 newtag->map_count = 0; 295 newtag->segments = NULL; 296 newtag->bounce_zone = NULL; 297 298 /* Take into account any restrictions imposed by our parent tag */ 299 if (parent != NULL) { 300 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 301 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 302 303 if (newtag->boundary == 0) { 304 newtag->boundary = parent->boundary; 305 } else if (parent->boundary != 0) { 306 newtag->boundary = MIN(parent->boundary, 307 newtag->boundary); 308 } 309 310 #ifdef notyet 311 newtag->alignment = MAX(parent->alignment, newtag->alignment); 312 #endif 313 314 if (newtag->filter == NULL) { 315 /* 316 * Short circuit looking at our parent directly 317 * since we have encapsulated all of its information 318 */ 319 newtag->filter = parent->filter; 320 newtag->filterarg = parent->filterarg; 321 newtag->parent = parent->parent; 322 } 323 if (newtag->parent != NULL) 324 parent->ref_count++; 325 } 326 327 if (newtag->lowaddr < ptoa(Maxmem)) 328 newtag->flags |= BUS_DMA_BOUNCE_LOWADDR; 329 if (bounce_alignment && newtag->alignment > 1 && 330 !(newtag->flags & BUS_DMA_ALIGNED)) 331 newtag->flags |= BUS_DMA_BOUNCE_ALIGN; 332 333 if ((newtag->flags & BUS_DMA_COULD_BOUNCE) && 334 (flags & BUS_DMA_ALLOCNOW) != 0) { 335 struct bounce_zone *bz; 336 337 /* Must bounce */ 338 339 error = alloc_bounce_zone(newtag); 340 if (error) 341 goto back; 342 bz = newtag->bounce_zone; 343 344 if ((newtag->flags & BUS_DMA_ALLOCALL) == 0 && 345 ptoa(bz->total_bpages) < maxsize) { 346 int pages; 347 348 if (flags & BUS_DMA_ONEBPAGE) { 349 pages = 1; 350 } else { 351 pages = atop(round_page(maxsize)) - 352 bz->total_bpages; 353 pages = MAX(pages, 1); 354 } 355 356 /* Add pages to our bounce pool */ 357 if (alloc_bounce_pages(newtag, pages, flags) < pages) 358 error = ENOMEM; 359 360 /* Performed initial allocation */ 361 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 362 } 363 } 364 back: 365 if (error) { 366 free_bounce_zone(newtag); 367 kfree(newtag, M_DEVBUF); 368 } else { 369 *dmat = newtag; 370 } 371 return error; 372 } 373 374 int 375 bus_dma_tag_destroy(bus_dma_tag_t dmat) 376 { 377 if (dmat != NULL) { 378 if (dmat->map_count != 0) 379 return (EBUSY); 380 381 while (dmat != NULL) { 382 bus_dma_tag_t parent; 383 384 parent = dmat->parent; 385 dmat->ref_count--; 386 if (dmat->ref_count == 0) { 387 free_bounce_zone(dmat); 388 if (dmat->segments != NULL) 389 kfree(dmat->segments, M_DEVBUF); 390 kfree(dmat, M_DEVBUF); 391 /* 392 * Last reference count, so 393 * release our reference 394 * count on our parent. 395 */ 396 dmat = parent; 397 } else 398 dmat = NULL; 399 } 400 } 401 return (0); 402 } 403 404 bus_size_t 405 bus_dma_tag_getmaxsize(bus_dma_tag_t tag) 406 { 407 return(tag->maxsize); 408 } 409 410 /* 411 * Allocate a handle for mapping from kva/uva/physical 412 * address space into bus device space. 413 */ 414 int 415 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 416 { 417 int error; 418 419 error = 0; 420 421 if (dmat->segments == NULL) { 422 KKASSERT(dmat->nsegments && dmat->nsegments < 16384); 423 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) * 424 dmat->nsegments, M_DEVBUF, M_INTWAIT); 425 } 426 427 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 428 struct bounce_zone *bz; 429 int maxpages; 430 431 /* Must bounce */ 432 433 if (dmat->bounce_zone == NULL) { 434 error = alloc_bounce_zone(dmat); 435 if (error) 436 return error; 437 } 438 bz = dmat->bounce_zone; 439 440 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO); 441 442 /* Initialize the new map */ 443 STAILQ_INIT(&((*mapp)->bpages)); 444 445 /* 446 * Attempt to add pages to our pool on a per-instance 447 * basis up to a sane limit. 448 */ 449 if (dmat->flags & BUS_DMA_ALLOCALL) { 450 maxpages = Maxmem - atop(dmat->lowaddr); 451 } else if (dmat->flags & BUS_DMA_BOUNCE_ALIGN) { 452 maxpages = max_bounce_pages; 453 } else { 454 maxpages = MIN(max_bounce_pages, 455 Maxmem - atop(dmat->lowaddr)); 456 } 457 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 || 458 (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 459 int pages; 460 461 if (flags & BUS_DMA_ONEBPAGE) { 462 pages = 1; 463 } else { 464 pages = atop(round_page(dmat->maxsize)); 465 pages = MIN(maxpages - bz->total_bpages, pages); 466 pages = MAX(pages, 1); 467 } 468 if (alloc_bounce_pages(dmat, pages, flags) < pages) 469 error = ENOMEM; 470 471 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 472 if (!error && 473 (dmat->flags & BUS_DMA_ALLOCALL) == 0) 474 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 475 } else { 476 error = 0; 477 } 478 } 479 } else { 480 *mapp = NULL; 481 } 482 if (!error) { 483 dmat->map_count++; 484 } else { 485 kfree(*mapp, M_DEVBUF); 486 *mapp = NULL; 487 } 488 return error; 489 } 490 491 /* 492 * Destroy a handle for mapping from kva/uva/physical 493 * address space into bus device space. 494 */ 495 int 496 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 497 { 498 if (map != NULL) { 499 if (STAILQ_FIRST(&map->bpages) != NULL) 500 return (EBUSY); 501 kfree(map, M_DEVBUF); 502 } 503 dmat->map_count--; 504 return (0); 505 } 506 507 static __inline bus_size_t 508 check_kmalloc(bus_dma_tag_t dmat, const void *vaddr0, int verify) 509 { 510 bus_size_t maxsize = 0; 511 uintptr_t vaddr = (uintptr_t)vaddr0; 512 513 if ((vaddr ^ (vaddr + dmat->maxsize - 1)) & ~PAGE_MASK) { 514 if (verify || bootverbose) 515 kprintf("boundary check failed\n"); 516 if (verify) 517 print_backtrace(-1); /* XXX panic */ 518 maxsize = dmat->maxsize; 519 } 520 if (vaddr & (dmat->alignment - 1)) { 521 if (verify || bootverbose) 522 kprintf("alignment check failed\n"); 523 if (verify) 524 print_backtrace(-1); /* XXX panic */ 525 if (dmat->maxsize < dmat->alignment) 526 maxsize = dmat->alignment; 527 else 528 maxsize = dmat->maxsize; 529 } 530 return maxsize; 531 } 532 533 /* 534 * Allocate a piece of memory that can be efficiently mapped into 535 * bus device space based on the constraints lited in the dma tag. 536 * 537 * mapp is degenerate. By definition this allocation should not require 538 * bounce buffers so do not allocate a dma map. 539 */ 540 int 541 bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags, 542 bus_dmamap_t *mapp) 543 { 544 int mflags; 545 546 /* If we succeed, no mapping/bouncing will be required */ 547 *mapp = NULL; 548 549 if (dmat->segments == NULL) { 550 KKASSERT(dmat->nsegments < 16384); 551 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) * 552 dmat->nsegments, M_DEVBUF, M_INTWAIT); 553 } 554 555 if (flags & BUS_DMA_NOWAIT) 556 mflags = M_NOWAIT; 557 else 558 mflags = M_WAITOK; 559 if (flags & BUS_DMA_ZERO) 560 mflags |= M_ZERO; 561 562 if (BUS_DMAMEM_KMALLOC(dmat)) { 563 bus_size_t maxsize; 564 565 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags); 566 567 /* 568 * XXX 569 * Check whether the allocation 570 * - crossed a page boundary 571 * - was not aligned 572 * Retry with power-of-2 alignment in the above cases. 573 */ 574 maxsize = check_kmalloc(dmat, *vaddr, 0); 575 if (maxsize) { 576 size_t size; 577 578 kfree(*vaddr, M_DEVBUF); 579 /* XXX check for overflow? */ 580 for (size = 1; size <= maxsize; size <<= 1) 581 ; 582 *vaddr = kmalloc(size, M_DEVBUF, mflags); 583 check_kmalloc(dmat, *vaddr, 1); 584 } 585 } else { 586 /* 587 * XXX Use Contigmalloc until it is merged into this facility 588 * and handles multi-seg allocations. Nobody is doing 589 * multi-seg allocations yet though. 590 */ 591 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 592 0ul, dmat->lowaddr, dmat->alignment, dmat->boundary); 593 } 594 if (*vaddr == NULL) 595 return (ENOMEM); 596 return (0); 597 } 598 599 /* 600 * Free a piece of memory and it's allociated dmamap, that was allocated 601 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 602 */ 603 void 604 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 605 { 606 /* 607 * dmamem does not need to be bounced, so the map should be 608 * NULL 609 */ 610 if (map != NULL) 611 panic("bus_dmamem_free: Invalid map freed"); 612 if (BUS_DMAMEM_KMALLOC(dmat)) 613 kfree(vaddr, M_DEVBUF); 614 else 615 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 616 } 617 618 static __inline vm_paddr_t 619 _bus_dma_extract(pmap_t pmap, vm_offset_t vaddr) 620 { 621 if (pmap) 622 return pmap_extract(pmap, vaddr); 623 else 624 return pmap_kextract(vaddr); 625 } 626 627 /* 628 * Utility function to load a linear buffer. lastaddrp holds state 629 * between invocations (for multiple-buffer loads). segp contains 630 * the segment following the starting one on entrace, and the ending 631 * segment on exit. first indicates if this is the first invocation 632 * of this function. 633 */ 634 static int 635 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 636 bus_dmamap_t map, 637 void *buf, bus_size_t buflen, 638 bus_dma_segment_t *segments, 639 int nsegments, 640 pmap_t pmap, 641 int flags, 642 vm_paddr_t *lastpaddrp, 643 int *segp, 644 int first) 645 { 646 vm_offset_t vaddr; 647 vm_paddr_t paddr, nextpaddr; 648 bus_dma_segment_t *sg; 649 bus_addr_t bmask; 650 int seg, error = 0; 651 652 if (map == NULL) 653 map = &nobounce_dmamap; 654 655 #ifdef INVARIANTS 656 if (dmat->flags & BUS_DMA_ALIGNED) 657 KKASSERT(((uintptr_t)buf & (dmat->alignment - 1)) == 0); 658 #endif 659 660 /* 661 * If we are being called during a callback, pagesneeded will 662 * be non-zero, so we can avoid doing the work twice. 663 */ 664 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) && 665 map != &nobounce_dmamap && map->pagesneeded == 0) { 666 vm_offset_t vendaddr; 667 668 /* 669 * Count the number of bounce pages 670 * needed in order to complete this transfer 671 */ 672 vaddr = (vm_offset_t)buf; 673 vendaddr = (vm_offset_t)buf + buflen; 674 675 while (vaddr < vendaddr) { 676 paddr = _bus_dma_extract(pmap, vaddr); 677 if (run_filter(dmat, paddr) != 0) 678 map->pagesneeded++; 679 vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK)); 680 } 681 } 682 683 /* Reserve Necessary Bounce Pages */ 684 if (map->pagesneeded != 0) { 685 struct bounce_zone *bz; 686 687 bz = dmat->bounce_zone; 688 BZ_LOCK(bz); 689 if (flags & BUS_DMA_NOWAIT) { 690 if (reserve_bounce_pages(dmat, map, 0) != 0) { 691 BZ_UNLOCK(bz); 692 error = ENOMEM; 693 goto free_bounce; 694 } 695 } else { 696 if (reserve_bounce_pages(dmat, map, 1) != 0) { 697 /* Queue us for resources */ 698 map->dmat = dmat; 699 map->buf = buf; 700 map->buflen = buflen; 701 702 STAILQ_INSERT_TAIL( 703 &dmat->bounce_zone->bounce_map_waitinglist, 704 map, links); 705 BZ_UNLOCK(bz); 706 707 return (EINPROGRESS); 708 } 709 } 710 BZ_UNLOCK(bz); 711 } 712 713 KKASSERT(*segp >= 1 && *segp <= nsegments); 714 seg = *segp; 715 sg = &segments[seg - 1]; 716 717 vaddr = (vm_offset_t)buf; 718 nextpaddr = *lastpaddrp; 719 bmask = ~(dmat->boundary - 1); /* note: will be 0 if boundary is 0 */ 720 721 /* force at least one segment */ 722 do { 723 bus_size_t size; 724 725 /* 726 * Per-page main loop 727 */ 728 paddr = _bus_dma_extract(pmap, vaddr); 729 size = PAGE_SIZE - (paddr & PAGE_MASK); 730 if (size > buflen) 731 size = buflen; 732 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) { 733 /* 734 * note: this paddr has the same in-page offset 735 * as vaddr and thus the paddr above, so the 736 * size does not have to be recalculated 737 */ 738 paddr = add_bounce_page(dmat, map, vaddr, size); 739 } 740 741 /* 742 * Fill in the bus_dma_segment 743 */ 744 if (first) { 745 sg->ds_addr = paddr; 746 sg->ds_len = size; 747 first = 0; 748 } else if (paddr == nextpaddr) { 749 sg->ds_len += size; 750 } else { 751 sg++; 752 seg++; 753 if (seg > nsegments) 754 break; 755 sg->ds_addr = paddr; 756 sg->ds_len = size; 757 } 758 nextpaddr = paddr + size; 759 760 /* 761 * Handle maxsegsz and boundary issues with a nested loop 762 */ 763 for (;;) { 764 bus_size_t tmpsize; 765 766 /* 767 * Limit to the boundary and maximum segment size 768 */ 769 if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) { 770 tmpsize = dmat->boundary - 771 (sg->ds_addr & ~bmask); 772 if (tmpsize > dmat->maxsegsz) 773 tmpsize = dmat->maxsegsz; 774 KKASSERT(tmpsize < sg->ds_len); 775 } else if (sg->ds_len > dmat->maxsegsz) { 776 tmpsize = dmat->maxsegsz; 777 } else { 778 break; 779 } 780 781 /* 782 * Futz, split the data into a new segment. 783 */ 784 if (seg >= nsegments) 785 goto fail; 786 sg[1].ds_len = sg[0].ds_len - tmpsize; 787 sg[1].ds_addr = sg[0].ds_addr + tmpsize; 788 sg[0].ds_len = tmpsize; 789 sg++; 790 seg++; 791 } 792 793 /* 794 * Adjust for loop 795 */ 796 buflen -= size; 797 vaddr += size; 798 } while (buflen > 0); 799 fail: 800 if (buflen != 0) 801 error = EFBIG; 802 803 *segp = seg; 804 *lastpaddrp = nextpaddr; 805 806 free_bounce: 807 if (error && (dmat->flags & BUS_DMA_COULD_BOUNCE) && 808 map != &nobounce_dmamap) { 809 _bus_dmamap_unload(dmat, map); 810 return_bounce_pages(dmat, map); 811 } 812 return error; 813 } 814 815 /* 816 * Map the buffer buf into bus space using the dmamap map. 817 */ 818 int 819 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 820 bus_size_t buflen, bus_dmamap_callback_t *callback, 821 void *callback_arg, int flags) 822 { 823 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS]; 824 bus_dma_segment_t *segments; 825 vm_paddr_t lastaddr = 0; 826 int error, nsegs = 1; 827 828 if (map != NULL) { 829 /* 830 * XXX 831 * Follow old semantics. Once all of the callers are fixed, 832 * we should get rid of these internal flag "adjustment". 833 */ 834 flags &= ~BUS_DMA_NOWAIT; 835 flags |= BUS_DMA_WAITOK; 836 837 map->callback = callback; 838 map->callback_arg = callback_arg; 839 } 840 841 segments = bus_dma_tag_lock(dmat, cache_segments); 842 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, 843 segments, dmat->nsegments, 844 NULL, flags, &lastaddr, &nsegs, 1); 845 if (error == EINPROGRESS) { 846 KKASSERT((dmat->flags & 847 (BUS_DMA_PRIVBZONE | BUS_DMA_ALLOCALL)) != 848 (BUS_DMA_PRIVBZONE | BUS_DMA_ALLOCALL)); 849 850 if (dmat->flags & BUS_DMA_PROTECTED) 851 panic("protected dmamap callback will be defered"); 852 853 bus_dma_tag_unlock(dmat); 854 return error; 855 } 856 callback(callback_arg, segments, nsegs, error); 857 bus_dma_tag_unlock(dmat); 858 return 0; 859 } 860 861 /* 862 * Like _bus_dmamap_load(), but for mbufs. 863 */ 864 int 865 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 866 struct mbuf *m0, 867 bus_dmamap_callback2_t *callback, void *callback_arg, 868 int flags) 869 { 870 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS]; 871 bus_dma_segment_t *segments; 872 int nsegs, error; 873 874 /* 875 * XXX 876 * Follow old semantics. Once all of the callers are fixed, 877 * we should get rid of these internal flag "adjustment". 878 */ 879 flags &= ~BUS_DMA_WAITOK; 880 flags |= BUS_DMA_NOWAIT; 881 882 segments = bus_dma_tag_lock(dmat, cache_segments); 883 error = bus_dmamap_load_mbuf_segment(dmat, map, m0, 884 segments, dmat->nsegments, &nsegs, flags); 885 if (error) { 886 /* force "no valid mappings" in callback */ 887 callback(callback_arg, segments, 0, 888 0, error); 889 } else { 890 callback(callback_arg, segments, nsegs, 891 m0->m_pkthdr.len, error); 892 } 893 bus_dma_tag_unlock(dmat); 894 return error; 895 } 896 897 int 898 bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat, bus_dmamap_t map, 899 struct mbuf *m0, 900 bus_dma_segment_t *segs, int maxsegs, 901 int *nsegs, int flags) 902 { 903 int error; 904 905 M_ASSERTPKTHDR(m0); 906 907 KASSERT(maxsegs >= 1, ("invalid maxsegs %d", maxsegs)); 908 KASSERT(maxsegs <= dmat->nsegments, 909 ("%d too many segments, dmat only supports %d segments", 910 maxsegs, dmat->nsegments)); 911 KASSERT(flags & BUS_DMA_NOWAIT, 912 ("only BUS_DMA_NOWAIT is supported")); 913 914 if (m0->m_pkthdr.len <= dmat->maxsize) { 915 int first = 1; 916 vm_paddr_t lastaddr = 0; 917 struct mbuf *m; 918 919 *nsegs = 1; 920 error = 0; 921 for (m = m0; m != NULL && error == 0; m = m->m_next) { 922 if (m->m_len == 0) 923 continue; 924 925 error = _bus_dmamap_load_buffer(dmat, map, 926 m->m_data, m->m_len, 927 segs, maxsegs, 928 NULL, flags, &lastaddr, 929 nsegs, first); 930 if (error == ENOMEM && !first) { 931 /* 932 * Out of bounce pages due to too many 933 * fragments in the mbuf chain; return 934 * EFBIG instead. 935 */ 936 error = EFBIG; 937 } 938 first = 0; 939 } 940 #ifdef INVARIANTS 941 if (!error) 942 KKASSERT(*nsegs <= maxsegs && *nsegs >= 1); 943 #endif 944 } else { 945 *nsegs = 0; 946 error = EINVAL; 947 } 948 KKASSERT(error != EINPROGRESS); 949 return error; 950 } 951 952 /* 953 * Like _bus_dmamap_load(), but for uios. 954 */ 955 int 956 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 957 struct uio *uio, 958 bus_dmamap_callback2_t *callback, void *callback_arg, 959 int flags) 960 { 961 vm_paddr_t lastaddr; 962 int nsegs, error, first, i; 963 bus_size_t resid; 964 struct iovec *iov; 965 pmap_t pmap; 966 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS]; 967 bus_dma_segment_t *segments; 968 bus_dma_segment_t *segs; 969 int nsegs_left; 970 971 if (dmat->nsegments <= BUS_DMA_CACHE_SEGMENTS) 972 segments = cache_segments; 973 else 974 segments = kmalloc(sizeof(bus_dma_segment_t) * dmat->nsegments, 975 M_DEVBUF, M_WAITOK | M_ZERO); 976 977 /* 978 * XXX 979 * Follow old semantics. Once all of the callers are fixed, 980 * we should get rid of these internal flag "adjustment". 981 */ 982 flags &= ~BUS_DMA_WAITOK; 983 flags |= BUS_DMA_NOWAIT; 984 985 resid = (bus_size_t)uio->uio_resid; 986 iov = uio->uio_iov; 987 988 segs = segments; 989 nsegs_left = dmat->nsegments; 990 991 if (uio->uio_segflg == UIO_USERSPACE) { 992 struct thread *td; 993 994 td = uio->uio_td; 995 KASSERT(td != NULL && td->td_proc != NULL, 996 ("bus_dmamap_load_uio: USERSPACE but no proc")); 997 pmap = vmspace_pmap(td->td_proc->p_vmspace); 998 } else { 999 pmap = NULL; 1000 } 1001 1002 error = 0; 1003 nsegs = 1; 1004 first = 1; 1005 lastaddr = 0; 1006 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 1007 /* 1008 * Now at the first iovec to load. Load each iovec 1009 * until we have exhausted the residual count. 1010 */ 1011 bus_size_t minlen = 1012 resid < iov[i].iov_len ? resid : iov[i].iov_len; 1013 caddr_t addr = (caddr_t) iov[i].iov_base; 1014 1015 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen, 1016 segs, nsegs_left, 1017 pmap, flags, &lastaddr, &nsegs, first); 1018 first = 0; 1019 1020 resid -= minlen; 1021 if (error == 0) { 1022 nsegs_left -= nsegs; 1023 segs += nsegs; 1024 } 1025 } 1026 1027 /* 1028 * Minimum one DMA segment, even if 0-length buffer. 1029 */ 1030 if (nsegs_left == dmat->nsegments) 1031 --nsegs_left; 1032 1033 if (error) { 1034 /* force "no valid mappings" in callback */ 1035 callback(callback_arg, segments, 0, 1036 0, error); 1037 } else { 1038 callback(callback_arg, segments, dmat->nsegments - nsegs_left, 1039 (bus_size_t)uio->uio_resid, error); 1040 } 1041 if (dmat->nsegments > BUS_DMA_CACHE_SEGMENTS) 1042 kfree(segments, M_DEVBUF); 1043 return error; 1044 } 1045 1046 /* 1047 * Release the mapping held by map. 1048 */ 1049 void 1050 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 1051 { 1052 struct bounce_page *bpage; 1053 1054 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 1055 STAILQ_REMOVE_HEAD(&map->bpages, links); 1056 free_bounce_page(dmat, bpage); 1057 } 1058 } 1059 1060 void 1061 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 1062 { 1063 struct bounce_page *bpage; 1064 1065 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 1066 /* 1067 * Handle data bouncing. We might also 1068 * want to add support for invalidating 1069 * the caches on broken hardware 1070 */ 1071 switch (op) { 1072 case BUS_DMASYNC_PREWRITE: 1073 while (bpage != NULL) { 1074 bcopy((void *)bpage->datavaddr, 1075 (void *)bpage->vaddr, 1076 bpage->datacount); 1077 bpage = STAILQ_NEXT(bpage, links); 1078 } 1079 dmat->bounce_zone->total_bounced++; 1080 break; 1081 1082 case BUS_DMASYNC_POSTREAD: 1083 while (bpage != NULL) { 1084 bcopy((void *)bpage->vaddr, 1085 (void *)bpage->datavaddr, 1086 bpage->datacount); 1087 bpage = STAILQ_NEXT(bpage, links); 1088 } 1089 dmat->bounce_zone->total_bounced++; 1090 break; 1091 1092 case BUS_DMASYNC_PREREAD: 1093 case BUS_DMASYNC_POSTWRITE: 1094 /* No-ops */ 1095 break; 1096 } 1097 } 1098 } 1099 1100 static int 1101 alloc_bounce_zone(bus_dma_tag_t dmat) 1102 { 1103 struct bounce_zone *bz, *new_bz; 1104 1105 KASSERT(dmat->bounce_zone == NULL, 1106 ("bounce zone was already assigned")); 1107 1108 new_bz = kmalloc(sizeof(*new_bz), M_DEVBUF, M_INTWAIT | M_ZERO); 1109 1110 lwkt_gettoken(&bounce_zone_tok); 1111 1112 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) { 1113 /* 1114 * For shared bounce zone, check to see 1115 * if we already have a suitable zone 1116 */ 1117 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1118 if (dmat->alignment <= bz->alignment && 1119 dmat->lowaddr >= bz->lowaddr) { 1120 lwkt_reltoken(&bounce_zone_tok); 1121 1122 dmat->bounce_zone = bz; 1123 kfree(new_bz, M_DEVBUF); 1124 return 0; 1125 } 1126 } 1127 } 1128 bz = new_bz; 1129 1130 #ifdef SMP 1131 spin_init(&bz->spin); 1132 #endif 1133 STAILQ_INIT(&bz->bounce_page_list); 1134 STAILQ_INIT(&bz->bounce_map_waitinglist); 1135 bz->free_bpages = 0; 1136 bz->reserved_bpages = 0; 1137 bz->active_bpages = 0; 1138 bz->lowaddr = dmat->lowaddr; 1139 bz->alignment = round_page(dmat->alignment); 1140 ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1141 1142 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) { 1143 ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1144 busdma_zonecount++; 1145 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1146 } else { 1147 ksnprintf(bz->zoneid, 8, "zone%d", busdma_priv_zonecount); 1148 busdma_priv_zonecount--; 1149 } 1150 1151 lwkt_reltoken(&bounce_zone_tok); 1152 1153 dmat->bounce_zone = bz; 1154 1155 sysctl_ctx_init(&bz->sysctl_ctx); 1156 bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx, 1157 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1158 CTLFLAG_RD, 0, ""); 1159 if (bz->sysctl_tree == NULL) { 1160 sysctl_ctx_free(&bz->sysctl_ctx); 1161 return 0; /* XXX error code? */ 1162 } 1163 1164 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1165 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1166 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1167 "Total bounce pages"); 1168 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1169 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1170 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1171 "Free bounce pages"); 1172 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1173 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1174 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1175 "Reserved bounce pages"); 1176 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1177 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1178 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1179 "Active bounce pages"); 1180 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1181 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1182 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1183 "Total bounce requests"); 1184 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1185 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1186 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1187 "Total bounce requests that were deferred"); 1188 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1189 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1190 "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0, 1191 "Total bounce page reservations that were failed"); 1192 SYSCTL_ADD_STRING(&bz->sysctl_ctx, 1193 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1194 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1195 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1196 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1197 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1198 1199 return 0; 1200 } 1201 1202 static int 1203 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages, int flags) 1204 { 1205 struct bounce_zone *bz = dmat->bounce_zone; 1206 int count = 0, mflags; 1207 1208 if (flags & BUS_DMA_NOWAIT) 1209 mflags = M_NOWAIT; 1210 else 1211 mflags = M_WAITOK; 1212 1213 while (numpages > 0) { 1214 struct bounce_page *bpage; 1215 1216 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO); 1217 1218 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1219 mflags, 0ul, 1220 bz->lowaddr, 1221 bz->alignment, 0); 1222 if (bpage->vaddr == 0) { 1223 kfree(bpage, M_DEVBUF); 1224 break; 1225 } 1226 bpage->busaddr = pmap_kextract(bpage->vaddr); 1227 1228 BZ_LOCK(bz); 1229 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1230 total_bounce_pages++; 1231 bz->total_bpages++; 1232 bz->free_bpages++; 1233 BZ_UNLOCK(bz); 1234 1235 count++; 1236 numpages--; 1237 } 1238 return count; 1239 } 1240 1241 static void 1242 free_bounce_pages_all(bus_dma_tag_t dmat) 1243 { 1244 struct bounce_zone *bz = dmat->bounce_zone; 1245 struct bounce_page *bpage; 1246 1247 BZ_LOCK(bz); 1248 1249 while ((bpage = STAILQ_FIRST(&bz->bounce_page_list)) != NULL) { 1250 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1251 1252 KKASSERT(total_bounce_pages > 0); 1253 total_bounce_pages--; 1254 1255 KKASSERT(bz->total_bpages > 0); 1256 bz->total_bpages--; 1257 1258 KKASSERT(bz->free_bpages > 0); 1259 bz->free_bpages--; 1260 1261 BZ_UNLOCK(bz); 1262 contigfree((void *)bpage->vaddr, PAGE_SIZE, M_DEVBUF); 1263 kfree(bpage, M_DEVBUF); 1264 BZ_LOCK(bz); 1265 } 1266 if (bz->total_bpages) { 1267 kprintf("#%d bounce pages are still in use\n", 1268 bz->total_bpages); 1269 print_backtrace(-1); 1270 } 1271 1272 BZ_UNLOCK(bz); 1273 } 1274 1275 static void 1276 free_bounce_zone(bus_dma_tag_t dmat) 1277 { 1278 struct bounce_zone *bz = dmat->bounce_zone; 1279 1280 if (bz == NULL) 1281 return; 1282 1283 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) 1284 return; 1285 1286 free_bounce_pages_all(dmat); 1287 dmat->bounce_zone = NULL; 1288 1289 if (bz->sysctl_tree != NULL) 1290 sysctl_ctx_free(&bz->sysctl_ctx); 1291 kfree(bz, M_DEVBUF); 1292 } 1293 1294 /* Assume caller holds bounce zone spinlock */ 1295 static int 1296 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1297 { 1298 struct bounce_zone *bz = dmat->bounce_zone; 1299 int pages; 1300 1301 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1302 if (!commit && map->pagesneeded > (map->pagesreserved + pages)) { 1303 bz->reserve_failed++; 1304 return (map->pagesneeded - (map->pagesreserved + pages)); 1305 } 1306 1307 bz->free_bpages -= pages; 1308 1309 bz->reserved_bpages += pages; 1310 KKASSERT(bz->reserved_bpages <= bz->total_bpages); 1311 1312 map->pagesreserved += pages; 1313 pages = map->pagesneeded - map->pagesreserved; 1314 1315 return pages; 1316 } 1317 1318 static void 1319 return_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map) 1320 { 1321 struct bounce_zone *bz = dmat->bounce_zone; 1322 int reserved = map->pagesreserved; 1323 bus_dmamap_t wait_map; 1324 1325 map->pagesreserved = 0; 1326 map->pagesneeded = 0; 1327 1328 if (reserved == 0) 1329 return; 1330 1331 BZ_LOCK(bz); 1332 1333 bz->free_bpages += reserved; 1334 KKASSERT(bz->free_bpages <= bz->total_bpages); 1335 1336 KKASSERT(bz->reserved_bpages >= reserved); 1337 bz->reserved_bpages -= reserved; 1338 1339 wait_map = get_map_waiting(dmat); 1340 1341 BZ_UNLOCK(bz); 1342 1343 if (wait_map != NULL) 1344 add_map_callback(map); 1345 } 1346 1347 static bus_addr_t 1348 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1349 bus_size_t size) 1350 { 1351 struct bounce_zone *bz = dmat->bounce_zone; 1352 struct bounce_page *bpage; 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 bpage->datavaddr = vaddr; 1375 bpage->datacount = size; 1376 STAILQ_INSERT_TAIL(&map->bpages, bpage, links); 1377 return bpage->busaddr; 1378 } 1379 1380 static void 1381 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1382 { 1383 struct bounce_zone *bz = dmat->bounce_zone; 1384 bus_dmamap_t map; 1385 1386 bpage->datavaddr = 0; 1387 bpage->datacount = 0; 1388 1389 BZ_LOCK(bz); 1390 1391 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1392 1393 bz->free_bpages++; 1394 KKASSERT(bz->free_bpages <= bz->total_bpages); 1395 1396 KKASSERT(bz->active_bpages > 0); 1397 bz->active_bpages--; 1398 1399 map = get_map_waiting(dmat); 1400 1401 BZ_UNLOCK(bz); 1402 1403 if (map != NULL) 1404 add_map_callback(map); 1405 } 1406 1407 /* Assume caller holds bounce zone spinlock */ 1408 static bus_dmamap_t 1409 get_map_waiting(bus_dma_tag_t dmat) 1410 { 1411 struct bounce_zone *bz = dmat->bounce_zone; 1412 bus_dmamap_t map; 1413 1414 map = STAILQ_FIRST(&bz->bounce_map_waitinglist); 1415 if (map != NULL) { 1416 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1417 STAILQ_REMOVE_HEAD(&bz->bounce_map_waitinglist, links); 1418 bz->total_deferred++; 1419 } else { 1420 map = NULL; 1421 } 1422 } 1423 return map; 1424 } 1425 1426 static void 1427 add_map_callback(bus_dmamap_t map) 1428 { 1429 spin_lock(&bounce_map_list_spin); 1430 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, map, links); 1431 busdma_swi_pending = 1; 1432 setsoftvm(); 1433 spin_unlock(&bounce_map_list_spin); 1434 } 1435 1436 void 1437 busdma_swi(void) 1438 { 1439 bus_dmamap_t map; 1440 1441 spin_lock(&bounce_map_list_spin); 1442 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1443 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1444 spin_unlock(&bounce_map_list_spin); 1445 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1446 map->callback, map->callback_arg, /*flags*/0); 1447 spin_lock(&bounce_map_list_spin); 1448 } 1449 spin_unlock(&bounce_map_list_spin); 1450 } 1451