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 * $DragonFly: src/sys/platform/pc32/i386/busdma_machdep.c,v 1.23 2008/06/05 18:06:32 swildner Exp $ 28 */ 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/malloc.h> 33 #include <sys/mbuf.h> 34 #include <sys/uio.h> 35 #include <sys/thread2.h> 36 #include <sys/bus_dma.h> 37 #include <sys/kernel.h> 38 #include <sys/sysctl.h> 39 #include <sys/lock.h> 40 #include <sys/spinlock2.h> 41 42 #include <vm/vm.h> 43 #include <vm/vm_page.h> 44 45 /* XXX needed for to access pmap to convert per-proc virtual to physical */ 46 #include <sys/proc.h> 47 #include <sys/lock.h> 48 #include <vm/vm_map.h> 49 50 #include <machine/md_var.h> 51 52 #define MAX_BPAGES 1024 53 54 struct bounce_zone; 55 struct bus_dmamap; 56 57 struct bus_dma_tag { 58 bus_dma_tag_t parent; 59 bus_size_t alignment; 60 bus_size_t boundary; 61 bus_addr_t lowaddr; 62 bus_addr_t highaddr; 63 bus_dma_filter_t *filter; 64 void *filterarg; 65 bus_size_t maxsize; 66 u_int nsegments; 67 bus_size_t maxsegsz; 68 int flags; 69 int ref_count; 70 int map_count; 71 bus_dma_segment_t *segments; 72 struct bounce_zone *bounce_zone; 73 }; 74 75 /* 76 * bus_dma_tag private flags 77 */ 78 #define BUS_DMA_BOUNCE_ALIGN BUS_DMA_BUS2 79 #define BUS_DMA_BOUNCE_LOWADDR BUS_DMA_BUS3 80 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 81 82 #define BUS_DMA_COULD_BOUNCE (BUS_DMA_BOUNCE_LOWADDR | BUS_DMA_BOUNCE_ALIGN) 83 84 #define BUS_DMAMEM_KMALLOC(dmat) \ 85 ((dmat)->maxsize <= PAGE_SIZE && \ 86 (dmat)->alignment <= PAGE_SIZE && \ 87 (dmat)->lowaddr >= ptoa(Maxmem)) 88 89 struct bounce_page { 90 vm_offset_t vaddr; /* kva of bounce buffer */ 91 bus_addr_t busaddr; /* Physical address */ 92 vm_offset_t datavaddr; /* kva of client data */ 93 bus_size_t datacount; /* client data count */ 94 STAILQ_ENTRY(bounce_page) links; 95 }; 96 97 struct bounce_zone { 98 STAILQ_ENTRY(bounce_zone) links; 99 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 100 STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 101 #ifdef SMP 102 struct spinlock spin; 103 #else 104 int unused0; 105 #endif 106 int total_bpages; 107 int free_bpages; 108 int reserved_bpages; 109 int active_bpages; 110 int total_bounced; 111 int total_deferred; 112 int reserve_failed; 113 bus_size_t alignment; 114 bus_addr_t lowaddr; 115 char zoneid[8]; 116 char lowaddrid[20]; 117 struct sysctl_ctx_list sysctl_ctx; 118 struct sysctl_oid *sysctl_tree; 119 }; 120 121 #ifdef SMP 122 #define BZ_LOCK(bz) spin_lock(&(bz)->spin) 123 #define BZ_UNLOCK(bz) spin_unlock(&(bz)->spin) 124 #else 125 #define BZ_LOCK(bz) crit_enter() 126 #define BZ_UNLOCK(bz) crit_exit() 127 #endif 128 129 static struct lwkt_token bounce_zone_tok = 130 LWKT_TOKEN_INITIALIZER(bounce_zone_token); 131 static int busdma_zonecount; 132 static STAILQ_HEAD(, bounce_zone) bounce_zone_list = 133 STAILQ_HEAD_INITIALIZER(bounce_zone_list); 134 135 int busdma_swi_pending; 136 static int total_bounce_pages; 137 static int max_bounce_pages = MAX_BPAGES; 138 static int bounce_alignment = 1; /* XXX temporary */ 139 140 TUNABLE_INT("hw.busdma.max_bpages", &max_bounce_pages); 141 TUNABLE_INT("hw.busdma.bounce_alignment", &bounce_alignment); 142 143 struct bus_dmamap { 144 struct bp_list bpages; 145 int pagesneeded; 146 int pagesreserved; 147 bus_dma_tag_t dmat; 148 void *buf; /* unmapped buffer pointer */ 149 bus_size_t buflen; /* unmapped buffer length */ 150 bus_dmamap_callback_t *callback; 151 void *callback_arg; 152 STAILQ_ENTRY(bus_dmamap) links; 153 }; 154 155 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist = 156 STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist); 157 158 static struct bus_dmamap nobounce_dmamap; 159 160 static int alloc_bounce_zone(bus_dma_tag_t); 161 static int alloc_bounce_pages(bus_dma_tag_t, u_int, int); 162 static int reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int); 163 static void return_bounce_pages(bus_dma_tag_t, bus_dmamap_t); 164 static bus_addr_t add_bounce_page(bus_dma_tag_t, bus_dmamap_t, 165 vm_offset_t, bus_size_t); 166 static void free_bounce_page(bus_dma_tag_t, struct bounce_page *); 167 168 static bus_dmamap_t get_map_waiting(bus_dma_tag_t); 169 static void add_map_callback(bus_dmamap_t); 170 171 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 172 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages, 173 0, "Total bounce pages"); 174 SYSCTL_INT(_hw_busdma, OID_AUTO, max_bpages, CTLFLAG_RD, &max_bounce_pages, 175 0, "Max bounce pages per bounce zone"); 176 SYSCTL_INT(_hw_busdma, OID_AUTO, bounce_alignment, CTLFLAG_RD, 177 &bounce_alignment, 0, "Obey alignment constraint"); 178 179 static __inline int 180 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 181 { 182 int retval; 183 184 retval = 0; 185 do { 186 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) || 187 (bounce_alignment && (paddr & (dmat->alignment - 1)) != 0)) 188 && (dmat->filter == NULL || 189 dmat->filter(dmat->filterarg, paddr) != 0)) 190 retval = 1; 191 192 dmat = dmat->parent; 193 } while (retval == 0 && dmat != NULL); 194 return (retval); 195 } 196 197 /* 198 * Allocate a device specific dma_tag. 199 */ 200 int 201 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 202 bus_size_t boundary, bus_addr_t lowaddr, 203 bus_addr_t highaddr, bus_dma_filter_t *filter, 204 void *filterarg, bus_size_t maxsize, int nsegments, 205 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat) 206 { 207 bus_dma_tag_t newtag; 208 int error = 0; 209 210 /* 211 * Sanity checks 212 */ 213 214 if (alignment == 0) 215 alignment = 1; 216 if (alignment & (alignment - 1)) 217 panic("alignment must be power of 2\n"); 218 219 if (boundary != 0) { 220 if (boundary & (boundary - 1)) 221 panic("boundary must be power of 2\n"); 222 if (boundary < maxsegsz) { 223 kprintf("boundary < maxsegsz:\n"); 224 print_backtrace(-1); 225 maxsegsz = boundary; 226 } 227 } 228 229 /* Return a NULL tag on failure */ 230 *dmat = NULL; 231 232 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT); 233 234 newtag->parent = parent; 235 newtag->alignment = alignment; 236 newtag->boundary = boundary; 237 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 238 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 239 newtag->filter = filter; 240 newtag->filterarg = filterarg; 241 newtag->maxsize = maxsize; 242 newtag->nsegments = nsegments; 243 newtag->maxsegsz = maxsegsz; 244 newtag->flags = flags; 245 newtag->ref_count = 1; /* Count ourself */ 246 newtag->map_count = 0; 247 newtag->segments = NULL; 248 newtag->bounce_zone = NULL; 249 250 /* Take into account any restrictions imposed by our parent tag */ 251 if (parent != NULL) { 252 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 253 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 254 255 if (newtag->boundary == 0) { 256 newtag->boundary = parent->boundary; 257 } else if (parent->boundary != 0) { 258 newtag->boundary = MIN(parent->boundary, 259 newtag->boundary); 260 } 261 262 #ifdef notyet 263 newtag->alignment = MAX(parent->alignment, newtag->alignment); 264 #endif 265 266 if (newtag->filter == NULL) { 267 /* 268 * Short circuit looking at our parent directly 269 * since we have encapsulated all of its information 270 */ 271 newtag->filter = parent->filter; 272 newtag->filterarg = parent->filterarg; 273 newtag->parent = parent->parent; 274 } 275 if (newtag->parent != NULL) 276 parent->ref_count++; 277 } 278 279 if (newtag->lowaddr < ptoa(Maxmem)) 280 newtag->flags |= BUS_DMA_BOUNCE_LOWADDR; 281 if (bounce_alignment && newtag->alignment > 1 && 282 !(newtag->flags & BUS_DMA_ALIGNED)) 283 newtag->flags |= BUS_DMA_BOUNCE_ALIGN; 284 285 if ((newtag->flags & BUS_DMA_COULD_BOUNCE) && 286 (flags & BUS_DMA_ALLOCNOW) != 0) { 287 struct bounce_zone *bz; 288 289 /* Must bounce */ 290 291 error = alloc_bounce_zone(newtag); 292 if (error) 293 goto back; 294 bz = newtag->bounce_zone; 295 296 if (ptoa(bz->total_bpages) < maxsize) { 297 int pages; 298 299 if (flags & BUS_DMA_ONEBPAGE) { 300 pages = 1; 301 } else { 302 pages = atop(round_page(maxsize)) - 303 bz->total_bpages; 304 pages = MAX(pages, 1); 305 } 306 307 /* Add pages to our bounce pool */ 308 if (alloc_bounce_pages(newtag, pages, flags) < pages) 309 error = ENOMEM; 310 311 /* Performed initial allocation */ 312 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 313 } 314 } 315 back: 316 if (error) 317 kfree(newtag, M_DEVBUF); 318 else 319 *dmat = newtag; 320 return error; 321 } 322 323 int 324 bus_dma_tag_destroy(bus_dma_tag_t dmat) 325 { 326 if (dmat != NULL) { 327 if (dmat->map_count != 0) 328 return (EBUSY); 329 330 while (dmat != NULL) { 331 bus_dma_tag_t parent; 332 333 parent = dmat->parent; 334 dmat->ref_count--; 335 if (dmat->ref_count == 0) { 336 if (dmat->segments != NULL) 337 kfree(dmat->segments, M_DEVBUF); 338 kfree(dmat, M_DEVBUF); 339 /* 340 * Last reference count, so 341 * release our reference 342 * count on our parent. 343 */ 344 dmat = parent; 345 } else 346 dmat = NULL; 347 } 348 } 349 return (0); 350 } 351 352 /* 353 * Allocate a handle for mapping from kva/uva/physical 354 * address space into bus device space. 355 */ 356 int 357 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 358 { 359 int error; 360 361 error = 0; 362 363 if (dmat->segments == NULL) { 364 KKASSERT(dmat->nsegments && dmat->nsegments < 16384); 365 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) * 366 dmat->nsegments, M_DEVBUF, M_INTWAIT); 367 } 368 369 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 370 struct bounce_zone *bz; 371 int maxpages; 372 373 /* Must bounce */ 374 375 if (dmat->bounce_zone == NULL) { 376 error = alloc_bounce_zone(dmat); 377 if (error) 378 return error; 379 } 380 bz = dmat->bounce_zone; 381 382 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO); 383 384 /* Initialize the new map */ 385 STAILQ_INIT(&((*mapp)->bpages)); 386 387 /* 388 * Attempt to add pages to our pool on a per-instance 389 * basis up to a sane limit. 390 */ 391 if (dmat->flags & BUS_DMA_BOUNCE_ALIGN) { 392 maxpages = max_bounce_pages; 393 } else { 394 maxpages = MIN(max_bounce_pages, 395 Maxmem - atop(dmat->lowaddr)); 396 } 397 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 398 || (dmat->map_count > 0 399 && bz->total_bpages < maxpages)) { 400 int pages; 401 402 if (flags & BUS_DMA_ONEBPAGE) { 403 pages = 1; 404 } else { 405 pages = atop(round_page(dmat->maxsize)); 406 pages = MIN(maxpages - bz->total_bpages, pages); 407 pages = MAX(pages, 1); 408 } 409 if (alloc_bounce_pages(dmat, pages, flags) < pages) 410 error = ENOMEM; 411 412 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 413 if (!error) 414 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 415 } else { 416 error = 0; 417 } 418 } 419 } else { 420 *mapp = NULL; 421 } 422 if (!error) 423 dmat->map_count++; 424 return error; 425 } 426 427 /* 428 * Destroy a handle for mapping from kva/uva/physical 429 * address space into bus device space. 430 */ 431 int 432 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 433 { 434 if (map != NULL) { 435 if (STAILQ_FIRST(&map->bpages) != NULL) 436 return (EBUSY); 437 kfree(map, M_DEVBUF); 438 } 439 dmat->map_count--; 440 return (0); 441 } 442 443 static __inline bus_size_t 444 check_kmalloc(bus_dma_tag_t dmat, const void *vaddr0, int verify) 445 { 446 bus_size_t maxsize = 0; 447 uintptr_t vaddr = (uintptr_t)vaddr0; 448 449 if ((vaddr ^ (vaddr + dmat->maxsize - 1)) & ~PAGE_MASK) { 450 kprintf("boundary check failed\n"); 451 if (verify) 452 print_backtrace(-1); /* XXX panic */ 453 maxsize = dmat->maxsize; 454 } 455 if (vaddr & (dmat->alignment - 1)) { 456 kprintf("alignment check failed\n"); 457 if (verify) 458 print_backtrace(-1); /* XXX panic */ 459 if (dmat->maxsize < dmat->alignment) 460 maxsize = dmat->alignment; 461 else 462 maxsize = dmat->maxsize; 463 } 464 return maxsize; 465 } 466 467 /* 468 * Allocate a piece of memory that can be efficiently mapped into 469 * bus device space based on the constraints lited in the dma tag. 470 * 471 * mapp is degenerate. By definition this allocation should not require 472 * bounce buffers so do not allocate a dma map. 473 */ 474 int 475 bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags, 476 bus_dmamap_t *mapp) 477 { 478 int mflags; 479 480 /* If we succeed, no mapping/bouncing will be required */ 481 *mapp = NULL; 482 483 if (dmat->segments == NULL) { 484 KKASSERT(dmat->nsegments < 16384); 485 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) * 486 dmat->nsegments, M_DEVBUF, M_INTWAIT); 487 } 488 489 if (flags & BUS_DMA_NOWAIT) 490 mflags = M_NOWAIT; 491 else 492 mflags = M_WAITOK; 493 if (flags & BUS_DMA_ZERO) 494 mflags |= M_ZERO; 495 496 if (BUS_DMAMEM_KMALLOC(dmat)) { 497 bus_size_t maxsize; 498 499 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags); 500 501 /* 502 * XXX 503 * Check whether the allocation 504 * - crossed a page boundary 505 * - was not aligned 506 * Retry with power-of-2 alignment in the above cases. 507 */ 508 maxsize = check_kmalloc(dmat, *vaddr, 0); 509 if (maxsize) { 510 size_t size; 511 512 kfree(*vaddr, M_DEVBUF); 513 /* XXX check for overflow? */ 514 for (size = 1; size <= maxsize; size <<= 1) 515 ; 516 *vaddr = kmalloc(size, M_DEVBUF, mflags); 517 check_kmalloc(dmat, *vaddr, 1); 518 } 519 } else { 520 /* 521 * XXX Use Contigmalloc until it is merged into this facility 522 * and handles multi-seg allocations. Nobody is doing 523 * multi-seg allocations yet though. 524 */ 525 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 526 0ul, dmat->lowaddr, dmat->alignment, dmat->boundary); 527 } 528 if (*vaddr == NULL) 529 return (ENOMEM); 530 return (0); 531 } 532 533 /* 534 * Free a piece of memory and it's allociated dmamap, that was allocated 535 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 536 */ 537 void 538 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 539 { 540 /* 541 * dmamem does not need to be bounced, so the map should be 542 * NULL 543 */ 544 if (map != NULL) 545 panic("bus_dmamem_free: Invalid map freed\n"); 546 if (BUS_DMAMEM_KMALLOC(dmat)) 547 kfree(vaddr, M_DEVBUF); 548 else 549 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 550 } 551 552 static __inline vm_paddr_t 553 _bus_dma_extract(pmap_t pmap, vm_offset_t vaddr) 554 { 555 if (pmap) 556 return pmap_extract(pmap, vaddr); 557 else 558 return pmap_kextract(vaddr); 559 } 560 561 /* 562 * Utility function to load a linear buffer. lastaddrp holds state 563 * between invocations (for multiple-buffer loads). segp contains 564 * the segment following the starting one on entrace, and the ending 565 * segment on exit. first indicates if this is the first invocation 566 * of this function. 567 */ 568 static int 569 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 570 bus_dmamap_t map, 571 void *buf, bus_size_t buflen, 572 bus_dma_segment_t *segments, 573 int nsegments, 574 pmap_t pmap, 575 int flags, 576 vm_paddr_t *lastpaddrp, 577 int *segp, 578 int first) 579 { 580 vm_offset_t vaddr; 581 vm_paddr_t paddr, nextpaddr; 582 bus_dma_segment_t *sg; 583 bus_addr_t bmask; 584 int seg, error = 0; 585 586 if (map == NULL) 587 map = &nobounce_dmamap; 588 589 #ifdef INVARIANTS 590 if (dmat->flags & BUS_DMA_ALIGNED) 591 KKASSERT(((uintptr_t)buf & (dmat->alignment - 1)) == 0); 592 #endif 593 594 /* 595 * If we are being called during a callback, pagesneeded will 596 * be non-zero, so we can avoid doing the work twice. 597 */ 598 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) && 599 map != &nobounce_dmamap && map->pagesneeded == 0) { 600 vm_offset_t vendaddr; 601 602 /* 603 * Count the number of bounce pages 604 * needed in order to complete this transfer 605 */ 606 vaddr = (vm_offset_t)buf; 607 vendaddr = (vm_offset_t)buf + buflen; 608 609 while (vaddr < vendaddr) { 610 paddr = _bus_dma_extract(pmap, vaddr); 611 if (run_filter(dmat, paddr) != 0) 612 map->pagesneeded++; 613 vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK)); 614 } 615 } 616 617 /* Reserve Necessary Bounce Pages */ 618 if (map->pagesneeded != 0) { 619 struct bounce_zone *bz; 620 621 bz = dmat->bounce_zone; 622 BZ_LOCK(bz); 623 if (flags & BUS_DMA_NOWAIT) { 624 if (reserve_bounce_pages(dmat, map, 0) != 0) { 625 BZ_UNLOCK(bz); 626 error = ENOMEM; 627 goto free_bounce; 628 } 629 } else { 630 if (reserve_bounce_pages(dmat, map, 1) != 0) { 631 /* Queue us for resources */ 632 map->dmat = dmat; 633 map->buf = buf; 634 map->buflen = buflen; 635 636 STAILQ_INSERT_TAIL( 637 &dmat->bounce_zone->bounce_map_waitinglist, 638 map, links); 639 BZ_UNLOCK(bz); 640 641 return (EINPROGRESS); 642 } 643 } 644 BZ_UNLOCK(bz); 645 } 646 647 KKASSERT(*segp >= 1 && *segp <= nsegments); 648 seg = *segp; 649 sg = &segments[seg - 1]; 650 651 vaddr = (vm_offset_t)buf; 652 nextpaddr = *lastpaddrp; 653 bmask = ~(dmat->boundary - 1); /* note: will be 0 if boundary is 0 */ 654 655 /* force at least one segment */ 656 do { 657 bus_size_t size; 658 659 /* 660 * Per-page main loop 661 */ 662 paddr = _bus_dma_extract(pmap, vaddr); 663 size = PAGE_SIZE - (paddr & PAGE_MASK); 664 if (size > buflen) 665 size = buflen; 666 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) { 667 /* 668 * note: this paddr has the same in-page offset 669 * as vaddr and thus the paddr above, so the 670 * size does not have to be recalculated 671 */ 672 paddr = add_bounce_page(dmat, map, vaddr, size); 673 } 674 675 /* 676 * Fill in the bus_dma_segment 677 */ 678 if (first) { 679 sg->ds_addr = paddr; 680 sg->ds_len = size; 681 first = 0; 682 } else if (paddr == nextpaddr) { 683 sg->ds_len += size; 684 } else { 685 sg++; 686 seg++; 687 if (seg > nsegments) 688 break; 689 sg->ds_addr = paddr; 690 sg->ds_len = size; 691 } 692 nextpaddr = paddr + size; 693 694 /* 695 * Handle maxsegsz and boundary issues with a nested loop 696 */ 697 for (;;) { 698 bus_size_t tmpsize; 699 700 /* 701 * Limit to the boundary and maximum segment size 702 */ 703 if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) { 704 tmpsize = dmat->boundary - 705 (sg->ds_addr & ~bmask); 706 if (tmpsize > dmat->maxsegsz) 707 tmpsize = dmat->maxsegsz; 708 KKASSERT(tmpsize < sg->ds_len); 709 } else if (sg->ds_len > dmat->maxsegsz) { 710 tmpsize = dmat->maxsegsz; 711 } else { 712 break; 713 } 714 715 /* 716 * Futz, split the data into a new segment. 717 */ 718 if (seg >= nsegments) 719 goto fail; 720 sg[1].ds_len = sg[0].ds_len - tmpsize; 721 sg[1].ds_addr = sg[0].ds_addr + tmpsize; 722 sg[0].ds_len = tmpsize; 723 sg++; 724 seg++; 725 } 726 727 /* 728 * Adjust for loop 729 */ 730 buflen -= size; 731 vaddr += size; 732 } while (buflen > 0); 733 fail: 734 if (buflen != 0) 735 error = EFBIG; 736 737 *segp = seg; 738 *lastpaddrp = nextpaddr; 739 740 free_bounce: 741 if (error && (dmat->flags & BUS_DMA_COULD_BOUNCE) && 742 map != &nobounce_dmamap) { 743 _bus_dmamap_unload(dmat, map); 744 return_bounce_pages(dmat, map); 745 } 746 return error; 747 } 748 749 /* 750 * Map the buffer buf into bus space using the dmamap map. 751 */ 752 int 753 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 754 bus_size_t buflen, bus_dmamap_callback_t *callback, 755 void *callback_arg, int flags) 756 { 757 vm_paddr_t lastaddr = 0; 758 int error, nsegs = 1; 759 760 if (map != NULL) { 761 /* 762 * XXX 763 * Follow old semantics. Once all of the callers are fixed, 764 * we should get rid of these internal flag "adjustment". 765 */ 766 flags &= ~BUS_DMA_NOWAIT; 767 flags |= BUS_DMA_WAITOK; 768 769 map->callback = callback; 770 map->callback_arg = callback_arg; 771 } 772 773 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, 774 dmat->segments, dmat->nsegments, 775 NULL, flags, &lastaddr, &nsegs, 1); 776 if (error == EINPROGRESS) 777 return error; 778 779 callback(callback_arg, dmat->segments, nsegs, error); 780 return 0; 781 } 782 783 /* 784 * Like _bus_dmamap_load(), but for mbufs. 785 */ 786 int 787 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 788 struct mbuf *m0, 789 bus_dmamap_callback2_t *callback, void *callback_arg, 790 int flags) 791 { 792 int nsegs, error; 793 794 /* 795 * XXX 796 * Follow old semantics. Once all of the callers are fixed, 797 * we should get rid of these internal flag "adjustment". 798 */ 799 flags &= ~BUS_DMA_WAITOK; 800 flags |= BUS_DMA_NOWAIT; 801 802 error = bus_dmamap_load_mbuf_segment(dmat, map, m0, 803 dmat->segments, dmat->nsegments, &nsegs, flags); 804 if (error) { 805 /* force "no valid mappings" in callback */ 806 callback(callback_arg, dmat->segments, 0, 0, error); 807 } else { 808 callback(callback_arg, dmat->segments, nsegs, 809 m0->m_pkthdr.len, error); 810 } 811 return error; 812 } 813 814 int 815 bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat, bus_dmamap_t map, 816 struct mbuf *m0, 817 bus_dma_segment_t *segs, int maxsegs, 818 int *nsegs, int flags) 819 { 820 int error; 821 822 M_ASSERTPKTHDR(m0); 823 824 KASSERT(maxsegs >= 1, ("invalid maxsegs %d\n", maxsegs)); 825 KASSERT(maxsegs <= dmat->nsegments, 826 ("%d too many segments, dmat only support %d segments\n", 827 maxsegs, dmat->nsegments)); 828 KASSERT(flags & BUS_DMA_NOWAIT, 829 ("only BUS_DMA_NOWAIT is supported\n")); 830 831 if (m0->m_pkthdr.len <= dmat->maxsize) { 832 int first = 1; 833 vm_paddr_t lastaddr = 0; 834 struct mbuf *m; 835 836 *nsegs = 1; 837 error = 0; 838 for (m = m0; m != NULL && error == 0; m = m->m_next) { 839 if (m->m_len == 0) 840 continue; 841 842 error = _bus_dmamap_load_buffer(dmat, map, 843 m->m_data, m->m_len, 844 segs, maxsegs, 845 NULL, flags, &lastaddr, 846 nsegs, first); 847 if (error == ENOMEM && !first) { 848 /* 849 * Out of bounce pages due to too many 850 * fragments in the mbuf chain; return 851 * EFBIG instead. 852 */ 853 error = EFBIG; 854 } 855 first = 0; 856 } 857 #ifdef INVARIANTS 858 if (!error) 859 KKASSERT(*nsegs <= maxsegs && *nsegs >= 1); 860 #endif 861 } else { 862 *nsegs = 0; 863 error = EINVAL; 864 } 865 KKASSERT(error != EINPROGRESS); 866 return error; 867 } 868 869 /* 870 * Like _bus_dmamap_load(), but for uios. 871 */ 872 int 873 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 874 struct uio *uio, 875 bus_dmamap_callback2_t *callback, void *callback_arg, 876 int flags) 877 { 878 vm_paddr_t lastaddr; 879 int nsegs, error, first, i; 880 bus_size_t resid; 881 struct iovec *iov; 882 pmap_t pmap; 883 884 /* 885 * XXX 886 * Follow old semantics. Once all of the callers are fixed, 887 * we should get rid of these internal flag "adjustment". 888 */ 889 flags &= ~BUS_DMA_WAITOK; 890 flags |= BUS_DMA_NOWAIT; 891 892 resid = (bus_size_t)uio->uio_resid; 893 iov = uio->uio_iov; 894 895 if (uio->uio_segflg == UIO_USERSPACE) { 896 struct thread *td; 897 898 td = uio->uio_td; 899 KASSERT(td != NULL && td->td_proc != NULL, 900 ("bus_dmamap_load_uio: USERSPACE but no proc")); 901 pmap = vmspace_pmap(td->td_proc->p_vmspace); 902 } else { 903 pmap = NULL; 904 } 905 906 error = 0; 907 nsegs = 1; 908 first = 1; 909 lastaddr = 0; 910 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 911 /* 912 * Now at the first iovec to load. Load each iovec 913 * until we have exhausted the residual count. 914 */ 915 bus_size_t minlen = 916 resid < iov[i].iov_len ? resid : iov[i].iov_len; 917 caddr_t addr = (caddr_t) iov[i].iov_base; 918 919 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen, 920 dmat->segments, dmat->nsegments, 921 pmap, flags, &lastaddr, &nsegs, first); 922 first = 0; 923 924 resid -= minlen; 925 } 926 927 if (error) { 928 /* force "no valid mappings" in callback */ 929 callback(callback_arg, dmat->segments, 0, 0, error); 930 } else { 931 callback(callback_arg, dmat->segments, nsegs, 932 (bus_size_t)uio->uio_resid, error); 933 } 934 return error; 935 } 936 937 /* 938 * Release the mapping held by map. 939 */ 940 void 941 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 942 { 943 struct bounce_page *bpage; 944 945 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 946 STAILQ_REMOVE_HEAD(&map->bpages, links); 947 free_bounce_page(dmat, bpage); 948 } 949 } 950 951 void 952 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 953 { 954 struct bounce_page *bpage; 955 956 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 957 /* 958 * Handle data bouncing. We might also 959 * want to add support for invalidating 960 * the caches on broken hardware 961 */ 962 switch (op) { 963 case BUS_DMASYNC_PREWRITE: 964 while (bpage != NULL) { 965 bcopy((void *)bpage->datavaddr, 966 (void *)bpage->vaddr, 967 bpage->datacount); 968 bpage = STAILQ_NEXT(bpage, links); 969 } 970 dmat->bounce_zone->total_bounced++; 971 break; 972 973 case BUS_DMASYNC_POSTREAD: 974 while (bpage != NULL) { 975 bcopy((void *)bpage->vaddr, 976 (void *)bpage->datavaddr, 977 bpage->datacount); 978 bpage = STAILQ_NEXT(bpage, links); 979 } 980 dmat->bounce_zone->total_bounced++; 981 break; 982 983 case BUS_DMASYNC_PREREAD: 984 case BUS_DMASYNC_POSTWRITE: 985 /* No-ops */ 986 break; 987 } 988 } 989 } 990 991 static int 992 alloc_bounce_zone(bus_dma_tag_t dmat) 993 { 994 struct bounce_zone *bz, *new_bz; 995 996 KASSERT(dmat->bounce_zone == NULL, 997 ("bounce zone was already assigned\n")); 998 999 new_bz = kmalloc(sizeof(*new_bz), M_DEVBUF, M_INTWAIT | M_ZERO); 1000 1001 lwkt_gettoken(&bounce_zone_tok); 1002 1003 /* Check to see if we already have a suitable zone */ 1004 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1005 if (dmat->alignment <= bz->alignment && 1006 dmat->lowaddr >= bz->lowaddr) { 1007 lwkt_reltoken(&bounce_zone_tok); 1008 1009 dmat->bounce_zone = bz; 1010 kfree(new_bz, M_DEVBUF); 1011 return 0; 1012 } 1013 } 1014 bz = new_bz; 1015 1016 #ifdef SMP 1017 spin_init(&bz->spin); 1018 #endif 1019 STAILQ_INIT(&bz->bounce_page_list); 1020 STAILQ_INIT(&bz->bounce_map_waitinglist); 1021 bz->free_bpages = 0; 1022 bz->reserved_bpages = 0; 1023 bz->active_bpages = 0; 1024 bz->lowaddr = dmat->lowaddr; 1025 bz->alignment = round_page(dmat->alignment); 1026 ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1027 busdma_zonecount++; 1028 ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1029 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1030 1031 lwkt_reltoken(&bounce_zone_tok); 1032 1033 dmat->bounce_zone = bz; 1034 1035 sysctl_ctx_init(&bz->sysctl_ctx); 1036 bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx, 1037 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1038 CTLFLAG_RD, 0, ""); 1039 if (bz->sysctl_tree == NULL) { 1040 sysctl_ctx_free(&bz->sysctl_ctx); 1041 return 0; /* XXX error code? */ 1042 } 1043 1044 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1045 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1046 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1047 "Total bounce pages"); 1048 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1049 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1050 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1051 "Free bounce pages"); 1052 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1053 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1054 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1055 "Reserved bounce pages"); 1056 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1057 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1058 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1059 "Active bounce pages"); 1060 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1061 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1062 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1063 "Total bounce requests"); 1064 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1065 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1066 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1067 "Total bounce requests that were deferred"); 1068 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1069 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1070 "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0, 1071 "Total bounce page reservations that were failed"); 1072 SYSCTL_ADD_STRING(&bz->sysctl_ctx, 1073 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1074 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1075 SYSCTL_ADD_INT(&bz->sysctl_ctx, 1076 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO, 1077 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1078 1079 return 0; 1080 } 1081 1082 static int 1083 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages, int flags) 1084 { 1085 struct bounce_zone *bz = dmat->bounce_zone; 1086 int count = 0, mflags; 1087 1088 if (flags & BUS_DMA_NOWAIT) 1089 mflags = M_NOWAIT; 1090 else 1091 mflags = M_WAITOK; 1092 1093 while (numpages > 0) { 1094 struct bounce_page *bpage; 1095 1096 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO); 1097 1098 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1099 mflags, 0ul, 1100 bz->lowaddr, 1101 bz->alignment, 0); 1102 if (bpage->vaddr == 0) { 1103 kfree(bpage, M_DEVBUF); 1104 break; 1105 } 1106 bpage->busaddr = pmap_kextract(bpage->vaddr); 1107 1108 BZ_LOCK(bz); 1109 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1110 total_bounce_pages++; 1111 bz->total_bpages++; 1112 bz->free_bpages++; 1113 BZ_UNLOCK(bz); 1114 1115 count++; 1116 numpages--; 1117 } 1118 return count; 1119 } 1120 1121 /* Assume caller holds bounce zone spinlock */ 1122 static int 1123 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1124 { 1125 struct bounce_zone *bz = dmat->bounce_zone; 1126 int pages; 1127 1128 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1129 if (!commit && map->pagesneeded > (map->pagesreserved + pages)) { 1130 bz->reserve_failed++; 1131 return (map->pagesneeded - (map->pagesreserved + pages)); 1132 } 1133 1134 bz->free_bpages -= pages; 1135 1136 bz->reserved_bpages += pages; 1137 KKASSERT(bz->reserved_bpages <= bz->total_bpages); 1138 1139 map->pagesreserved += pages; 1140 pages = map->pagesneeded - map->pagesreserved; 1141 1142 return pages; 1143 } 1144 1145 static void 1146 return_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map) 1147 { 1148 struct bounce_zone *bz = dmat->bounce_zone; 1149 int reserved = map->pagesreserved; 1150 bus_dmamap_t wait_map; 1151 1152 map->pagesreserved = 0; 1153 map->pagesneeded = 0; 1154 1155 if (reserved == 0) 1156 return; 1157 1158 BZ_LOCK(bz); 1159 1160 bz->free_bpages += reserved; 1161 KKASSERT(bz->free_bpages <= bz->total_bpages); 1162 1163 KKASSERT(bz->reserved_bpages >= reserved); 1164 bz->reserved_bpages -= reserved; 1165 1166 wait_map = get_map_waiting(dmat); 1167 1168 BZ_UNLOCK(bz); 1169 1170 if (wait_map != NULL) 1171 add_map_callback(map); 1172 } 1173 1174 static bus_addr_t 1175 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1176 bus_size_t size) 1177 { 1178 struct bounce_zone *bz = dmat->bounce_zone; 1179 struct bounce_page *bpage; 1180 1181 KASSERT(map->pagesneeded > 0, ("map doesn't need any pages")); 1182 map->pagesneeded--; 1183 1184 KASSERT(map->pagesreserved > 0, ("map doesn't reserve any pages")); 1185 map->pagesreserved--; 1186 1187 BZ_LOCK(bz); 1188 1189 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1190 KASSERT(bpage != NULL, ("free page list is empty")); 1191 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1192 1193 KKASSERT(bz->reserved_bpages > 0); 1194 bz->reserved_bpages--; 1195 1196 bz->active_bpages++; 1197 KKASSERT(bz->active_bpages <= bz->total_bpages); 1198 1199 BZ_UNLOCK(bz); 1200 1201 bpage->datavaddr = vaddr; 1202 bpage->datacount = size; 1203 STAILQ_INSERT_TAIL(&map->bpages, bpage, links); 1204 return bpage->busaddr; 1205 } 1206 1207 static void 1208 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1209 { 1210 struct bounce_zone *bz = dmat->bounce_zone; 1211 bus_dmamap_t map; 1212 1213 bpage->datavaddr = 0; 1214 bpage->datacount = 0; 1215 1216 BZ_LOCK(bz); 1217 1218 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1219 1220 bz->free_bpages++; 1221 KKASSERT(bz->free_bpages <= bz->total_bpages); 1222 1223 KKASSERT(bz->active_bpages > 0); 1224 bz->active_bpages--; 1225 1226 map = get_map_waiting(dmat); 1227 1228 BZ_UNLOCK(bz); 1229 1230 if (map != NULL) 1231 add_map_callback(map); 1232 } 1233 1234 /* Assume caller holds bounce zone spinlock */ 1235 static bus_dmamap_t 1236 get_map_waiting(bus_dma_tag_t dmat) 1237 { 1238 struct bounce_zone *bz = dmat->bounce_zone; 1239 bus_dmamap_t map; 1240 1241 map = STAILQ_FIRST(&bz->bounce_map_waitinglist); 1242 if (map != NULL) { 1243 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1244 STAILQ_REMOVE_HEAD(&bz->bounce_map_waitinglist, links); 1245 bz->total_deferred++; 1246 } else { 1247 map = NULL; 1248 } 1249 } 1250 return map; 1251 } 1252 1253 static void 1254 add_map_callback(bus_dmamap_t map) 1255 { 1256 #ifdef notyet 1257 /* XXX callbacklist is not MPSAFE */ 1258 crit_enter(); 1259 get_mplock(); 1260 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, map, links); 1261 busdma_swi_pending = 1; 1262 setsoftvm(); 1263 rel_mplock(); 1264 crit_exit(); 1265 #else 1266 panic("%s uncoded\n", __func__); 1267 #endif 1268 } 1269 1270 #ifdef notyet 1271 void 1272 busdma_swi(void) 1273 { 1274 bus_dmamap_t map; 1275 1276 crit_enter(); 1277 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1278 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1279 crit_exit(); 1280 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1281 map->callback, map->callback_arg, /*flags*/0); 1282 crit_enter(); 1283 } 1284 crit_exit(); 1285 } 1286 #endif 1287