busdma_machdep.c revision 137445
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 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/i386/i386/busdma_machdep.c 137445 2004-11-09 07:07:54Z scottl $"); 29 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/malloc.h> 33#include <sys/bus.h> 34#include <sys/interrupt.h> 35#include <sys/kernel.h> 36#include <sys/ktr.h> 37#include <sys/lock.h> 38#include <sys/proc.h> 39#include <sys/mutex.h> 40#include <sys/mbuf.h> 41#include <sys/uio.h> 42#include <sys/sysctl.h> 43#include <sys/ktr.h> 44 45#include <vm/vm.h> 46#include <vm/vm_page.h> 47#include <vm/vm_map.h> 48 49#include <machine/atomic.h> 50#include <machine/bus.h> 51#include <machine/md_var.h> 52 53#define MAX_BPAGES 512 54 55struct bounce_zone; 56 57struct 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_lock_t *lockfunc; 72 void *lockfuncarg; 73 bus_dma_segment_t *segments; 74 struct bounce_zone *bounce_zone; 75}; 76 77struct bounce_page { 78 vm_offset_t vaddr; /* kva of bounce buffer */ 79 bus_addr_t busaddr; /* Physical address */ 80 vm_offset_t datavaddr; /* kva of client data */ 81 bus_size_t datacount; /* client data count */ 82 STAILQ_ENTRY(bounce_page) links; 83}; 84 85int busdma_swi_pending; 86 87struct bounce_zone { 88 STAILQ_ENTRY(bounce_zone) links; 89 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 90 int free_bpages; 91 int reserved_bpages; 92 int active_bpages; 93 int total_bounced; 94 int total_deferred; 95 bus_size_t alignment; 96 bus_size_t boundary; 97 bus_addr_t lowaddr; 98 char zoneid[8]; 99 char lowaddrid[20]; 100 struct sysctl_ctx_list sysctl_tree; 101 struct sysctl_oid *sysctl_tree_top; 102}; 103 104static struct mtx bounce_lock; 105static int total_bpages; 106static int busdma_zonecount; 107static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 108static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR; 109 110SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 111SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 112 "Total bounce pages"); 113 114struct bus_dmamap { 115 struct bp_list bpages; 116 int pagesneeded; 117 int pagesreserved; 118 bus_dma_tag_t dmat; 119 void *buf; /* unmapped buffer pointer */ 120 bus_size_t buflen; /* unmapped buffer length */ 121 bus_dmamap_callback_t *callback; 122 void *callback_arg; 123 STAILQ_ENTRY(bus_dmamap) links; 124}; 125 126static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 127static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 128static struct bus_dmamap nobounce_dmamap; 129 130static void init_bounce_pages(void *dummy); 131static struct bounce_zone * alloc_bounce_zone(bus_dma_tag_t dmat); 132static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 133static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 134 int commit); 135static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 136 vm_offset_t vaddr, bus_size_t size); 137static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 138static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr, 139 bus_size_t len); 140 141/* 142 * Return true if a match is made. 143 * 144 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 145 * 146 * If paddr is within the bounds of the dma tag then call the filter callback 147 * to check for a match, if there is no filter callback then assume a match. 148 */ 149static __inline int 150run_filter(bus_dma_tag_t dmat, bus_addr_t paddr, bus_size_t len) 151{ 152 bus_size_t bndy; 153 int retval; 154 155 retval = 0; 156 bndy = dmat->boundary; 157 158 do { 159 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 160 || ((paddr & (dmat->alignment - 1)) != 0) 161 || ((paddr & bndy) != ((paddr + len) & bndy))) 162 && (dmat->filter == NULL 163 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 164 retval = 1; 165 166 dmat = dmat->parent; 167 } while (retval == 0 && dmat != NULL); 168 return (retval); 169} 170 171/* 172 * Convenience function for manipulating driver locks from busdma (during 173 * busdma_swi, for example). Drivers that don't provide their own locks 174 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 175 * non-mutex locking scheme don't have to use this at all. 176 */ 177void 178busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 179{ 180 struct mtx *dmtx; 181 182 dmtx = (struct mtx *)arg; 183 switch (op) { 184 case BUS_DMA_LOCK: 185 mtx_lock(dmtx); 186 break; 187 case BUS_DMA_UNLOCK: 188 mtx_unlock(dmtx); 189 break; 190 default: 191 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 192 } 193} 194 195/* 196 * dflt_lock should never get called. It gets put into the dma tag when 197 * lockfunc == NULL, which is only valid if the maps that are associated 198 * with the tag are meant to never be defered. 199 * XXX Should have a way to identify which driver is responsible here. 200 */ 201static void 202dflt_lock(void *arg, bus_dma_lock_op_t op) 203{ 204 panic("driver error: busdma dflt_lock called"); 205} 206 207#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 208/* 209 * Allocate a device specific dma_tag. 210 */ 211int 212bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 213 bus_size_t boundary, bus_addr_t lowaddr, 214 bus_addr_t highaddr, bus_dma_filter_t *filter, 215 void *filterarg, bus_size_t maxsize, int nsegments, 216 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 217 void *lockfuncarg, bus_dma_tag_t *dmat) 218{ 219 bus_dma_tag_t newtag; 220 int error = 0; 221 222 /* Basic sanity checking */ 223 if (boundary != 0 && boundary < maxsegsz) 224 maxsegsz = boundary; 225 226 /* Return a NULL tag on failure */ 227 *dmat = NULL; 228 229 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, M_NOWAIT); 230 if (newtag == NULL) { 231 CTR3(KTR_BUSDMA, "bus_dma_tag_create returned tag %p tag " 232 "flags 0x%x error %d", newtag, 0, error); 233 return (ENOMEM); 234 } 235 236 newtag->parent = parent; 237 newtag->alignment = alignment; 238 newtag->boundary = boundary; 239 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 240 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 241 (PAGE_SIZE - 1); 242 newtag->filter = filter; 243 newtag->filterarg = filterarg; 244 newtag->maxsize = maxsize; 245 newtag->nsegments = nsegments; 246 newtag->maxsegsz = maxsegsz; 247 newtag->flags = flags; 248 newtag->ref_count = 1; /* Count ourself */ 249 newtag->map_count = 0; 250 if (lockfunc != NULL) { 251 newtag->lockfunc = lockfunc; 252 newtag->lockfuncarg = lockfuncarg; 253 } else { 254 newtag->lockfunc = dflt_lock; 255 newtag->lockfuncarg = NULL; 256 } 257 newtag->segments = NULL; 258 259 /* Take into account any restrictions imposed by our parent tag */ 260 if (parent != NULL) { 261 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 262 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 263 if (newtag->boundary == 0) 264 newtag->boundary = parent->boundary; 265 else if (parent->boundary != 0) 266 newtag->boundary = MIN(parent->boundary, 267 newtag->boundary); 268 if (newtag->filter == NULL) { 269 /* 270 * Short circuit looking at our parent directly 271 * since we have encapsulated all of its information 272 */ 273 newtag->filter = parent->filter; 274 newtag->filterarg = parent->filterarg; 275 newtag->parent = parent->parent; 276 } 277 if (newtag->parent != NULL) 278 atomic_add_int(&parent->ref_count, 1); 279 } 280 281 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && 282 (flags & BUS_DMA_ALLOCNOW) != 0) { 283 /* Must bounce */ 284 285 if (lowaddr > bounce_lowaddr) { 286 /* 287 * Go through the pool and kill any pages 288 * that don't reside below lowaddr. 289 */ 290 panic("bus_dma_tag_create: page reallocation " 291 "not implemented"); 292 } 293 if (ptoa(total_bpages) < maxsize) { 294 int pages; 295 296 pages = atop(maxsize) - total_bpages; 297 298 /* Add pages to our bounce pool */ 299 if (alloc_bounce_pages(newtag, pages) < pages) 300 error = ENOMEM; 301 } 302 /* Performed initial allocation */ 303 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 304 } 305 306 if (error != 0) { 307 free(newtag, M_DEVBUF); 308 } else { 309 *dmat = newtag; 310 } 311 CTR3(KTR_BUSDMA, "bus_dma_tag_create returned tag %p tag flags 0x%x " 312 "error %d", newtag, (newtag != NULL ? newtag->flags : 0), error); 313 return (error); 314} 315 316int 317bus_dma_tag_destroy(bus_dma_tag_t dmat) 318{ 319 bus_dma_tag_t dmat_copy; 320 int error; 321 322 error = 0; 323 dmat_copy = dmat; 324 325 if (dmat != NULL) { 326 327 if (dmat->map_count != 0) { 328 error = EBUSY; 329 goto out; 330 } 331 332 while (dmat != NULL) { 333 bus_dma_tag_t parent; 334 335 parent = dmat->parent; 336 atomic_subtract_int(&dmat->ref_count, 1); 337 if (dmat->ref_count == 0) { 338 if (dmat->segments != NULL) 339 free(dmat->segments, M_DEVBUF); 340 free(dmat, M_DEVBUF); 341 /* 342 * Last reference count, so 343 * release our reference 344 * count on our parent. 345 */ 346 dmat = parent; 347 } else 348 dmat = NULL; 349 } 350 } 351out: 352 CTR2(KTR_BUSDMA, "bus_dma_tag_destroy tag %p error %d", dmat_copy, 353 error); 354 return (error); 355} 356 357/* 358 * Allocate a handle for mapping from kva/uva/physical 359 * address space into bus device space. 360 */ 361int 362bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 363{ 364 int error; 365 366 error = 0; 367 368 if (dmat->segments == NULL) { 369 dmat->segments = (bus_dma_segment_t *)malloc( 370 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 371 M_NOWAIT); 372 if (dmat->segments == NULL) { 373 CTR2(KTR_BUSDMA, "bus_dmamap_create: tag %p error %d", 374 dmat, ENOMEM); 375 return (ENOMEM); 376 } 377 } 378 379 /* 380 * Bouncing might be required if the driver asks for an active 381 * exclusion region, a data alignment that is stricter than 1, and/or 382 * an active address boundary. 383 */ 384 if (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) 385 || dmat->alignment > 1 || dmat->boundary > 0) { 386 387 /* Must bounce */ 388 int maxpages; 389 390 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 391 M_NOWAIT | M_ZERO); 392 if (*mapp == NULL) { 393 CTR2(KTR_BUSDMA, "bus_dmamap_create: tag %p error %d", 394 dmat, ENOMEM); 395 return (ENOMEM); 396 } 397 398 /* Initialize the new map */ 399 STAILQ_INIT(&((*mapp)->bpages)); 400 401 /* 402 * Attempt to add pages to our pool on a per-instance 403 * basis up to a sane limit. 404 */ 405 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr)); 406 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 407 || (dmat->map_count > 0 && total_bpages < maxpages)) { 408 int pages; 409 410 if (dmat->lowaddr > bounce_lowaddr) { 411 /* 412 * Go through the pool and kill any pages 413 * that don't reside below lowaddr. 414 */ 415 panic("bus_dmamap_create: page reallocation " 416 "not implemented"); 417 } 418 pages = MAX(atop(dmat->maxsize), 1); 419 pages = MIN(maxpages - total_bpages, pages); 420 if (alloc_bounce_pages(dmat, pages) < pages) 421 error = ENOMEM; 422 423 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 424 if (error == 0) 425 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 426 } else { 427 error = 0; 428 } 429 } 430 } else { 431 *mapp = NULL; 432 } 433 if (error == 0) 434 dmat->map_count++; 435 CTR3(KTR_BUSDMA, "bus_dmamap_create: tag %p tag flags 0x%x error %d", 436 dmat, dmat->flags, error); 437 return (error); 438} 439 440/* 441 * Destroy a handle for mapping from kva/uva/physical 442 * address space into bus device space. 443 */ 444int 445bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 446{ 447 if (map != NULL && map != &nobounce_dmamap) { 448 if (STAILQ_FIRST(&map->bpages) != NULL) { 449 CTR2(KTR_BUSDMA, "bus_dmamap_destroy: tag %p error %d", 450 dmat, EBUSY); 451 return (EBUSY); 452 } 453 free(map, M_DEVBUF); 454 } 455 dmat->map_count--; 456 CTR1(KTR_BUSDMA, "bus_dmamap_destroy: tag %p error 0", dmat); 457 return (0); 458} 459 460 461/* 462 * Allocate a piece of memory that can be efficiently mapped into 463 * bus device space based on the constraints lited in the dma tag. 464 * A dmamap to for use with dmamap_load is also allocated. 465 */ 466int 467bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 468 bus_dmamap_t *mapp) 469{ 470 int mflags; 471 472 if (flags & BUS_DMA_NOWAIT) 473 mflags = M_NOWAIT; 474 else 475 mflags = M_WAITOK; 476 if (flags & BUS_DMA_ZERO) 477 mflags |= M_ZERO; 478 479 /* If we succeed, no mapping/bouncing will be required */ 480 *mapp = NULL; 481 482 if (dmat->segments == NULL) { 483 dmat->segments = (bus_dma_segment_t *)malloc( 484 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 485 M_NOWAIT); 486 if (dmat->segments == NULL) { 487 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag " 488 "flags 0x%x error %d", dmat, dmat->flags, ENOMEM); 489 return (ENOMEM); 490 } 491 } 492 493 if ((dmat->maxsize <= PAGE_SIZE) && 494 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 495 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 496 } else { 497 /* 498 * XXX Use Contigmalloc until it is merged into this facility 499 * and handles multi-seg allocations. Nobody is doing 500 * multi-seg allocations yet though. 501 * XXX Certain AGP hardware does. 502 */ 503 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 504 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 505 dmat->boundary); 506 } 507 if (*vaddr == NULL) { 508 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag flags 0x%x " 509 "error %d", dmat, dmat->flags, ENOMEM); 510 return (ENOMEM); 511 } 512 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag flags 0x%x error %d", 513 dmat, dmat->flags, ENOMEM); 514 return (0); 515} 516 517/* 518 * Free a piece of memory and it's allociated dmamap, that was allocated 519 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 520 */ 521void 522bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 523{ 524 /* 525 * dmamem does not need to be bounced, so the map should be 526 * NULL 527 */ 528 if (map != NULL) 529 panic("bus_dmamem_free: Invalid map freed\n"); 530 if ((dmat->maxsize <= PAGE_SIZE) 531 && dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 532 free(vaddr, M_DEVBUF); 533 else { 534 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 535 } 536 CTR2(KTR_BUSDMA, "bus_dmamem_free: tag %p flags 0x%x", dmat, 537 dmat->flags); 538} 539 540/* 541 * Utility function to load a linear buffer. lastaddrp holds state 542 * between invocations (for multiple-buffer loads). segp contains 543 * the starting segment on entrace, and the ending segment on exit. 544 * first indicates if this is the first invocation of this function. 545 */ 546static __inline int 547_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 548 bus_dmamap_t map, 549 void *buf, bus_size_t buflen, 550 pmap_t pmap, 551 int flags, 552 bus_addr_t *lastaddrp, 553 int *segp, 554 int first) 555{ 556 bus_dma_segment_t *segs; 557 bus_size_t sgsize; 558 bus_addr_t curaddr, lastaddr, baddr, bmask; 559 vm_offset_t vaddr; 560 bus_addr_t paddr; 561 int needbounce = 0; 562 int seg; 563 564 segs = dmat->segments; 565 566 if (map == NULL) 567 map = &nobounce_dmamap; 568 569 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 570 && (dmat->lowaddr < ptoa((vm_paddr_t)Maxmem) 571 || dmat->boundary > 0 || dmat->alignment > 1)) { 572 vm_offset_t vendaddr; 573 574 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 575 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 576 dmat->boundary, dmat->alignment); 577 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 578 map, &nobounce_dmamap, map->pagesneeded); 579 /* 580 * Count the number of bounce pages 581 * needed in order to complete this transfer 582 */ 583 vaddr = trunc_page((vm_offset_t)buf); 584 vendaddr = (vm_offset_t)buf + buflen; 585 586 while (vaddr < vendaddr) { 587 paddr = pmap_kextract(vaddr); 588 if (run_filter(dmat, paddr, 0) != 0) { 589 needbounce = 1; 590 map->pagesneeded++; 591 } 592 vaddr += PAGE_SIZE; 593 } 594 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 595 } 596 597 /* Reserve Necessary Bounce Pages */ 598 if (map->pagesneeded != 0) { 599 mtx_lock(&bounce_lock); 600 if (flags & BUS_DMA_NOWAIT) { 601 if (reserve_bounce_pages(dmat, map, 0) != 0) { 602 mtx_unlock(&bounce_lock); 603 return (ENOMEM); 604 } 605 } else { 606 if (reserve_bounce_pages(dmat, map, 1) != 0) { 607 /* Queue us for resources */ 608 map->dmat = dmat; 609 map->buf = buf; 610 map->buflen = buflen; 611 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 612 map, links); 613 mtx_unlock(&bounce_lock); 614 return (EINPROGRESS); 615 } 616 } 617 mtx_unlock(&bounce_lock); 618 } 619 620 vaddr = (vm_offset_t)buf; 621 lastaddr = *lastaddrp; 622 bmask = ~(dmat->boundary - 1); 623 624 for (seg = *segp; buflen > 0 ; ) { 625 /* 626 * Get the physical address for this segment. 627 */ 628 if (pmap) 629 curaddr = pmap_extract(pmap, vaddr); 630 else 631 curaddr = pmap_kextract(vaddr); 632 633 /* 634 * Compute the segment size, and adjust counts. 635 */ 636 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 637 if (buflen < sgsize) 638 sgsize = buflen; 639 640 /* 641 * Make sure we don't cross any boundaries. 642 */ 643 if (dmat->boundary > 0) { 644 baddr = (curaddr + dmat->boundary) & bmask; 645 if (sgsize > (baddr - curaddr)) 646 sgsize = (baddr - curaddr); 647 } 648 649 if (map->pagesneeded != 0 && run_filter(dmat, curaddr, sgsize)) 650 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 651 652 /* 653 * Insert chunk into a segment, coalescing with 654 * previous segment if possible. 655 */ 656 if (first) { 657 segs[seg].ds_addr = curaddr; 658 segs[seg].ds_len = sgsize; 659 first = 0; 660 } else { 661 if (needbounce == 0 && curaddr == lastaddr && 662 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 663 (dmat->boundary == 0 || 664 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 665 segs[seg].ds_len += sgsize; 666 else { 667 if (++seg >= dmat->nsegments) 668 break; 669 segs[seg].ds_addr = curaddr; 670 segs[seg].ds_len = sgsize; 671 } 672 } 673 674 lastaddr = curaddr + sgsize; 675 vaddr += sgsize; 676 buflen -= sgsize; 677 } 678 679 *segp = seg; 680 *lastaddrp = lastaddr; 681 682 /* 683 * Did we fit? 684 */ 685 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 686} 687 688/* 689 * Map the buffer buf into bus space using the dmamap map. 690 */ 691int 692bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 693 bus_size_t buflen, bus_dmamap_callback_t *callback, 694 void *callback_arg, int flags) 695{ 696 bus_addr_t lastaddr = 0; 697 int error, nsegs = 0; 698 699 if (map != NULL) { 700 flags |= BUS_DMA_WAITOK; 701 map->callback = callback; 702 map->callback_arg = callback_arg; 703 } 704 705 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 706 &lastaddr, &nsegs, 1); 707 708 if (error == EINPROGRESS) { 709 CTR3(KTR_BUSDMA, "bus_dmamap_load: tag %p tag flags 0x%x " 710 "error %d", dmat, dmat->flags, error); 711 return (error); 712 } 713 714 if (error) 715 (*callback)(callback_arg, dmat->segments, 0, error); 716 else 717 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 718 719 CTR2(KTR_BUSDMA, "bus_dmamap_load: tag %p tag flags 0x%x error 0", 720 dmat, dmat->flags); 721 return (0); 722} 723 724 725/* 726 * Like _bus_dmamap_load(), but for mbufs. 727 */ 728int 729bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 730 struct mbuf *m0, 731 bus_dmamap_callback2_t *callback, void *callback_arg, 732 int flags) 733{ 734 int nsegs, error; 735 736 M_ASSERTPKTHDR(m0); 737 738 flags |= BUS_DMA_NOWAIT; 739 nsegs = 0; 740 error = 0; 741 if (m0->m_pkthdr.len <= dmat->maxsize) { 742 int first = 1; 743 bus_addr_t lastaddr = 0; 744 struct mbuf *m; 745 746 for (m = m0; m != NULL && error == 0; m = m->m_next) { 747 if (m->m_len > 0) { 748 error = _bus_dmamap_load_buffer(dmat, map, 749 m->m_data, m->m_len, 750 NULL, flags, &lastaddr, 751 &nsegs, first); 752 first = 0; 753 } 754 } 755 } else { 756 error = EINVAL; 757 } 758 759 if (error) { 760 /* force "no valid mappings" in callback */ 761 (*callback)(callback_arg, dmat->segments, 0, 0, error); 762 } else { 763 (*callback)(callback_arg, dmat->segments, 764 nsegs+1, m0->m_pkthdr.len, error); 765 } 766 CTR3(KTR_BUSDMA, "bus_dmamap_load_mbuf: tag %p tag flags 0x%x " 767 "error %d", dmat, dmat->flags, error); 768 return (error); 769} 770 771/* 772 * Like _bus_dmamap_load(), but for uios. 773 */ 774int 775bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 776 struct uio *uio, 777 bus_dmamap_callback2_t *callback, void *callback_arg, 778 int flags) 779{ 780 bus_addr_t lastaddr; 781 int nsegs, error, first, i; 782 bus_size_t resid; 783 struct iovec *iov; 784 pmap_t pmap; 785 786 flags |= BUS_DMA_NOWAIT; 787 resid = uio->uio_resid; 788 iov = uio->uio_iov; 789 790 if (uio->uio_segflg == UIO_USERSPACE) { 791 KASSERT(uio->uio_td != NULL, 792 ("bus_dmamap_load_uio: USERSPACE but no proc")); 793 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 794 } else 795 pmap = NULL; 796 797 nsegs = 0; 798 error = 0; 799 first = 1; 800 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 801 /* 802 * Now at the first iovec to load. Load each iovec 803 * until we have exhausted the residual count. 804 */ 805 bus_size_t minlen = 806 resid < iov[i].iov_len ? resid : iov[i].iov_len; 807 caddr_t addr = (caddr_t) iov[i].iov_base; 808 809 if (minlen > 0) { 810 error = _bus_dmamap_load_buffer(dmat, map, 811 addr, minlen, 812 pmap, flags, &lastaddr, &nsegs, first); 813 first = 0; 814 815 resid -= minlen; 816 } 817 } 818 819 if (error) { 820 /* force "no valid mappings" in callback */ 821 (*callback)(callback_arg, dmat->segments, 0, 0, error); 822 } else { 823 (*callback)(callback_arg, dmat->segments, 824 nsegs+1, uio->uio_resid, error); 825 } 826 CTR3(KTR_BUSDMA, "bus_dmamap_load_uio: tag %p tag flags 0x%x " 827 "error %d", dmat, dmat->flags, error); 828 return (error); 829} 830 831/* 832 * Release the mapping held by map. 833 */ 834void 835_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 836{ 837 struct bounce_page *bpage; 838 839 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 840 STAILQ_REMOVE_HEAD(&map->bpages, links); 841 free_bounce_page(dmat, bpage); 842 } 843} 844 845void 846_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 847{ 848 struct bounce_page *bpage; 849 850 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 851 /* 852 * Handle data bouncing. We might also 853 * want to add support for invalidating 854 * the caches on broken hardware 855 */ 856 dmat->bounce_zone->total_bounced++; 857 CTR3(KTR_BUSDMA, "_bus_dmamap_sync: tag %p tag flags 0x%x " 858 "op 0x%x performing bounce", op, dmat, dmat->flags); 859 860 if (op & BUS_DMASYNC_PREWRITE) { 861 while (bpage != NULL) { 862 bcopy((void *)bpage->datavaddr, 863 (void *)bpage->vaddr, 864 bpage->datacount); 865 bpage = STAILQ_NEXT(bpage, links); 866 } 867 } 868 869 if (op & BUS_DMASYNC_POSTREAD) { 870 while (bpage != NULL) { 871 bcopy((void *)bpage->vaddr, 872 (void *)bpage->datavaddr, 873 bpage->datacount); 874 bpage = STAILQ_NEXT(bpage, links); 875 } 876 } 877 } 878} 879 880static void 881init_bounce_pages(void *dummy __unused) 882{ 883 884 total_bpages = 0; 885 STAILQ_INIT(&bounce_zone_list); 886 STAILQ_INIT(&bounce_map_waitinglist); 887 STAILQ_INIT(&bounce_map_callbacklist); 888 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 889} 890SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 891 892static struct sysctl_ctx_list * 893busdma_sysctl_tree(struct bounce_zone *bz) 894{ 895 return (&bz->sysctl_tree); 896} 897 898static struct sysctl_oid * 899busdma_sysctl_tree_top(struct bounce_zone *bz) 900{ 901 return (bz->sysctl_tree_top); 902} 903 904static struct bounce_zone * 905alloc_bounce_zone(bus_dma_tag_t dmat) 906{ 907 struct bounce_zone *bz; 908 909 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 910 M_NOWAIT | M_ZERO)) == NULL) 911 return (NULL); 912 913 STAILQ_INIT(&bz->bounce_page_list); 914 bz->free_bpages = 0; 915 bz->reserved_bpages = 0; 916 bz->active_bpages = 0; 917 bz->lowaddr = dmat->lowaddr; 918 bz->alignment = dmat->alignment; 919 bz->boundary = dmat->boundary; 920 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 921 busdma_zonecount++; 922 snprintf(bz->lowaddrid, 18, "%#jx", bz->lowaddr); 923 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 924 925 sysctl_ctx_init(&bz->sysctl_tree); 926 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 927 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 928 CTLFLAG_RD, 0, ""); 929 if (bz->sysctl_tree_top == NULL) { 930 sysctl_ctx_free(&bz->sysctl_tree); 931 return (bz); 932 } 933 934 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 935 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 936 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 937 "Free bounce pages"); 938 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 939 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 940 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 941 "Reserved bounce pages"); 942 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 943 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 944 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 945 "Active bounce pages"); 946 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 947 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 948 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 949 "Total bounce requests"); 950 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 951 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 952 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 953 "Total bounce requests that were deferred"); 954 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 955 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 956 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 957 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 958 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 959 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 960 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 961 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 962 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 963 964 return (bz); 965} 966 967static int 968alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 969{ 970 struct bounce_zone *bz; 971 int count; 972 973 bz = dmat->bounce_zone; 974 if (bz == NULL) { 975 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 976 if ((dmat->alignment <= bz->alignment) 977 && (dmat->boundary <= bz->boundary) 978 && (dmat->lowaddr >= bz->lowaddr)) 979 break; 980 } 981 982 if (bz == NULL) { 983 if ((bz = alloc_bounce_zone(dmat)) == NULL) 984 return (ENOMEM); 985 } 986 dmat->bounce_zone = bz; 987 } 988 989 count = 0; 990 while (numpages > 0) { 991 struct bounce_page *bpage; 992 993 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 994 M_NOWAIT | M_ZERO); 995 996 if (bpage == NULL) 997 break; 998 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 999 M_NOWAIT, 0ul, 1000 bz->lowaddr, 1001 PAGE_SIZE, 1002 bz->boundary); 1003 if (bpage->vaddr == 0) { 1004 free(bpage, M_DEVBUF); 1005 break; 1006 } 1007 bpage->busaddr = pmap_kextract(bpage->vaddr); 1008 mtx_lock(&bounce_lock); 1009 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1010 total_bpages++; 1011 bz->free_bpages++; 1012 mtx_unlock(&bounce_lock); 1013 count++; 1014 numpages--; 1015 } 1016 return (count); 1017} 1018 1019static int 1020reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1021{ 1022 struct bounce_zone *bz; 1023 int pages; 1024 1025 mtx_assert(&bounce_lock, MA_OWNED); 1026 bz = dmat->bounce_zone; 1027 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1028 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1029 return (map->pagesneeded - (map->pagesreserved + pages)); 1030 bz->free_bpages -= pages; 1031 bz->reserved_bpages += pages; 1032 map->pagesreserved += pages; 1033 pages = map->pagesneeded - map->pagesreserved; 1034 1035 return (pages); 1036} 1037 1038static bus_addr_t 1039add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1040 bus_size_t size) 1041{ 1042 struct bounce_zone *bz; 1043 struct bounce_page *bpage; 1044 1045 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1046 KASSERT(map != NULL && map != &nobounce_dmamap, 1047 ("add_bounce_page: bad map %p", map)); 1048 1049 bz = dmat->bounce_zone; 1050 if (map->pagesneeded == 0) 1051 panic("add_bounce_page: map doesn't need any pages"); 1052 map->pagesneeded--; 1053 1054 if (map->pagesreserved == 0) 1055 panic("add_bounce_page: map doesn't need any pages"); 1056 map->pagesreserved--; 1057 1058 mtx_lock(&bounce_lock); 1059 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1060 if (bpage == NULL) 1061 panic("add_bounce_page: free page list is empty"); 1062 1063 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1064 bz->reserved_bpages--; 1065 bz->active_bpages++; 1066 mtx_unlock(&bounce_lock); 1067 1068 bpage->datavaddr = vaddr; 1069 bpage->datacount = size; 1070 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1071 return (bpage->busaddr); 1072} 1073 1074static void 1075free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1076{ 1077 struct bus_dmamap *map; 1078 struct bounce_zone *bz; 1079 1080 bz = dmat->bounce_zone; 1081 bpage->datavaddr = 0; 1082 bpage->datacount = 0; 1083 1084 mtx_lock(&bounce_lock); 1085 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1086 bz->free_bpages++; 1087 bz->active_bpages--; 1088 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1089 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1090 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1091 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1092 map, links); 1093 busdma_swi_pending = 1; 1094 bz->total_deferred++; 1095 swi_sched(vm_ih, 0); 1096 } 1097 } 1098 mtx_unlock(&bounce_lock); 1099} 1100 1101void 1102busdma_swi(void) 1103{ 1104 bus_dma_tag_t dmat; 1105 struct bus_dmamap *map; 1106 1107 mtx_lock(&bounce_lock); 1108 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1109 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1110 mtx_unlock(&bounce_lock); 1111 dmat = map->dmat; 1112 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1113 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1114 map->callback, map->callback_arg, /*flags*/0); 1115 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1116 mtx_lock(&bounce_lock); 1117 } 1118 mtx_unlock(&bounce_lock); 1119} 1120