busdma_machdep.c revision 139840
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 139840 2005-01-07 07:57:18Z 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 44#include <vm/vm.h> 45#include <vm/vm_page.h> 46#include <vm/vm_map.h> 47 48#include <machine/atomic.h> 49#include <machine/bus.h> 50#include <machine/md_var.h> 51 52#define MAX_BPAGES 512 53 54struct bounce_zone; 55 56struct bus_dma_tag { 57 bus_dma_tag_t parent; 58 bus_size_t alignment; 59 bus_size_t boundary; 60 bus_addr_t lowaddr; 61 bus_addr_t highaddr; 62 bus_dma_filter_t *filter; 63 void *filterarg; 64 bus_size_t maxsize; 65 u_int nsegments; 66 bus_size_t maxsegsz; 67 int flags; 68 int ref_count; 69 int map_count; 70 bus_dma_lock_t *lockfunc; 71 void *lockfuncarg; 72 bus_dma_segment_t *segments; 73 struct bounce_zone *bounce_zone; 74}; 75 76struct bounce_page { 77 vm_offset_t vaddr; /* kva of bounce buffer */ 78 bus_addr_t busaddr; /* Physical address */ 79 vm_offset_t datavaddr; /* kva of client data */ 80 bus_size_t datacount; /* client data count */ 81 STAILQ_ENTRY(bounce_page) links; 82}; 83 84int busdma_swi_pending; 85 86struct bounce_zone { 87 STAILQ_ENTRY(bounce_zone) links; 88 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 89 int total_bpages; 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 int 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); 139 140/* 141 * Return true if a match is made. 142 * 143 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 144 * 145 * If paddr is within the bounds of the dma tag then call the filter callback 146 * to check for a match, if there is no filter callback then assume a match. 147 */ 148static __inline int 149run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 150{ 151 int retval; 152 153 retval = 0; 154 155 do { 156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 157 || ((paddr & (dmat->alignment - 1)) != 0)) 158 && (dmat->filter == NULL 159 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 160 retval = 1; 161 162 dmat = dmat->parent; 163 } while (retval == 0 && dmat != NULL); 164 return (retval); 165} 166 167/* 168 * Convenience function for manipulating driver locks from busdma (during 169 * busdma_swi, for example). Drivers that don't provide their own locks 170 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 171 * non-mutex locking scheme don't have to use this at all. 172 */ 173void 174busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 175{ 176 struct mtx *dmtx; 177 178 dmtx = (struct mtx *)arg; 179 switch (op) { 180 case BUS_DMA_LOCK: 181 mtx_lock(dmtx); 182 break; 183 case BUS_DMA_UNLOCK: 184 mtx_unlock(dmtx); 185 break; 186 default: 187 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 188 } 189} 190 191/* 192 * dflt_lock should never get called. It gets put into the dma tag when 193 * lockfunc == NULL, which is only valid if the maps that are associated 194 * with the tag are meant to never be defered. 195 * XXX Should have a way to identify which driver is responsible here. 196 */ 197static void 198dflt_lock(void *arg, bus_dma_lock_op_t op) 199{ 200 panic("driver error: busdma dflt_lock called"); 201} 202 203#define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 204#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 205/* 206 * Allocate a device specific dma_tag. 207 */ 208int 209bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 210 bus_size_t boundary, bus_addr_t lowaddr, 211 bus_addr_t highaddr, bus_dma_filter_t *filter, 212 void *filterarg, bus_size_t maxsize, int nsegments, 213 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 214 void *lockfuncarg, bus_dma_tag_t *dmat) 215{ 216 bus_dma_tag_t newtag; 217 int error = 0; 218 219 /* Basic sanity checking */ 220 if (boundary != 0 && boundary < maxsegsz) 221 maxsegsz = boundary; 222 223 /* Return a NULL tag on failure */ 224 *dmat = NULL; 225 226 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 227 M_ZERO | M_NOWAIT); 228 if (newtag == NULL) { 229 CTR3(KTR_BUSDMA, "bus_dma_tag_create returned tag %p tag " 230 "flags 0x%x error %d", newtag, 0, error); 231 return (ENOMEM); 232 } 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) + 239 (PAGE_SIZE - 1); 240 newtag->filter = filter; 241 newtag->filterarg = filterarg; 242 newtag->maxsize = maxsize; 243 newtag->nsegments = nsegments; 244 newtag->maxsegsz = maxsegsz; 245 newtag->flags = flags; 246 newtag->ref_count = 1; /* Count ourself */ 247 newtag->map_count = 0; 248 if (lockfunc != NULL) { 249 newtag->lockfunc = lockfunc; 250 newtag->lockfuncarg = lockfuncarg; 251 } else { 252 newtag->lockfunc = dflt_lock; 253 newtag->lockfuncarg = NULL; 254 } 255 newtag->segments = NULL; 256 257 /* Take into account any restrictions imposed by our parent tag */ 258 if (parent != NULL) { 259 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 260 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 261 if (newtag->boundary == 0) 262 newtag->boundary = parent->boundary; 263 else if (parent->boundary != 0) 264 newtag->boundary = MIN(parent->boundary, 265 newtag->boundary); 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 atomic_add_int(&parent->ref_count, 1); 277 } 278 279 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 280 || newtag->alignment > 1) 281 newtag->flags |= BUS_DMA_COULD_BOUNCE; 282 283 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 284 (flags & BUS_DMA_ALLOCNOW) != 0) { 285 struct bounce_zone *bz; 286 287 /* Must bounce */ 288 289 if ((error = alloc_bounce_zone(newtag)) != 0) 290 return (error); 291 bz = newtag->bounce_zone; 292 293 if (lowaddr > bounce_lowaddr) { 294 /* 295 * Go through the pool and kill any pages 296 * that don't reside below lowaddr. 297 */ 298 panic("bus_dma_tag_create: page reallocation " 299 "not implemented"); 300 } 301 if (ptoa(bz->total_bpages) < maxsize) { 302 int pages; 303 304 pages = atop(maxsize) - bz->total_bpages; 305 306 /* Add pages to our bounce pool */ 307 if (alloc_bounce_pages(newtag, pages) < pages) 308 error = ENOMEM; 309 } 310 /* Performed initial allocation */ 311 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 312 } 313 314 if (error != 0) { 315 free(newtag, M_DEVBUF); 316 } else { 317 *dmat = newtag; 318 } 319 CTR3(KTR_BUSDMA, "bus_dma_tag_create returned tag %p tag flags 0x%x " 320 "error %d", newtag, (newtag != NULL ? newtag->flags : 0), error); 321 return (error); 322} 323 324int 325bus_dma_tag_destroy(bus_dma_tag_t dmat) 326{ 327 bus_dma_tag_t dmat_copy; 328 int error; 329 330 error = 0; 331 dmat_copy = dmat; 332 333 if (dmat != NULL) { 334 335 if (dmat->map_count != 0) { 336 error = EBUSY; 337 goto out; 338 } 339 340 while (dmat != NULL) { 341 bus_dma_tag_t parent; 342 343 parent = dmat->parent; 344 atomic_subtract_int(&dmat->ref_count, 1); 345 if (dmat->ref_count == 0) { 346 if (dmat->segments != NULL) 347 free(dmat->segments, M_DEVBUF); 348 free(dmat, M_DEVBUF); 349 /* 350 * Last reference count, so 351 * release our reference 352 * count on our parent. 353 */ 354 dmat = parent; 355 } else 356 dmat = NULL; 357 } 358 } 359out: 360 CTR2(KTR_BUSDMA, "bus_dma_tag_destroy tag %p error %d", dmat_copy, 361 error); 362 return (error); 363} 364 365/* 366 * Allocate a handle for mapping from kva/uva/physical 367 * address space into bus device space. 368 */ 369int 370bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 371{ 372 int error; 373 374 error = 0; 375 376 if (dmat->segments == NULL) { 377 dmat->segments = (bus_dma_segment_t *)malloc( 378 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 379 M_NOWAIT); 380 if (dmat->segments == NULL) { 381 CTR2(KTR_BUSDMA, "bus_dmamap_create: tag %p error %d", 382 dmat, ENOMEM); 383 return (ENOMEM); 384 } 385 } 386 387 /* 388 * Bouncing might be required if the driver asks for an active 389 * exclusion region, a data alignment that is stricter than 1, and/or 390 * an active address boundary. 391 */ 392 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 393 394 /* Must bounce */ 395 int maxpages; 396 397 if (dmat->bounce_zone == NULL) { 398 if ((error = alloc_bounce_zone(dmat)) != 0) 399 return (error); 400 } 401 402 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 403 M_NOWAIT | M_ZERO); 404 if (*mapp == NULL) { 405 CTR2(KTR_BUSDMA, "bus_dmamap_create: tag %p error %d", 406 dmat, ENOMEM); 407 return (ENOMEM); 408 } 409 410 /* Initialize the new map */ 411 STAILQ_INIT(&((*mapp)->bpages)); 412 413 /* 414 * Attempt to add pages to our pool on a per-instance 415 * basis up to a sane limit. 416 */ 417 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr)); 418 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 419 || (dmat->map_count > 0 && total_bpages < maxpages)) { 420 int pages; 421 422 if (dmat->lowaddr > bounce_lowaddr) { 423 /* 424 * Go through the pool and kill any pages 425 * that don't reside below lowaddr. 426 */ 427 panic("bus_dmamap_create: page reallocation " 428 "not implemented"); 429 } 430 pages = MAX(atop(dmat->maxsize), 1); 431 pages = MIN(maxpages - total_bpages, pages); 432 if (alloc_bounce_pages(dmat, pages) < pages) 433 error = ENOMEM; 434 435 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 436 if (error == 0) 437 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 438 } else { 439 error = 0; 440 } 441 } 442 } else { 443 *mapp = NULL; 444 } 445 if (error == 0) 446 dmat->map_count++; 447 CTR3(KTR_BUSDMA, "bus_dmamap_create: tag %p tag flags 0x%x error %d", 448 dmat, dmat->flags, error); 449 return (error); 450} 451 452/* 453 * Destroy a handle for mapping from kva/uva/physical 454 * address space into bus device space. 455 */ 456int 457bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 458{ 459 if (map != NULL && map != &nobounce_dmamap) { 460 if (STAILQ_FIRST(&map->bpages) != NULL) { 461 CTR2(KTR_BUSDMA, "bus_dmamap_destroy: tag %p error %d", 462 dmat, EBUSY); 463 return (EBUSY); 464 } 465 free(map, M_DEVBUF); 466 } 467 dmat->map_count--; 468 CTR1(KTR_BUSDMA, "bus_dmamap_destroy: tag %p error 0", dmat); 469 return (0); 470} 471 472 473/* 474 * Allocate a piece of memory that can be efficiently mapped into 475 * bus device space based on the constraints lited in the dma tag. 476 * A dmamap to for use with dmamap_load is also allocated. 477 */ 478int 479bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 480 bus_dmamap_t *mapp) 481{ 482 int mflags; 483 484 if (flags & BUS_DMA_NOWAIT) 485 mflags = M_NOWAIT; 486 else 487 mflags = M_WAITOK; 488 if (flags & BUS_DMA_ZERO) 489 mflags |= M_ZERO; 490 491 /* If we succeed, no mapping/bouncing will be required */ 492 *mapp = NULL; 493 494 if (dmat->segments == NULL) { 495 dmat->segments = (bus_dma_segment_t *)malloc( 496 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 497 M_NOWAIT); 498 if (dmat->segments == NULL) { 499 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag " 500 "flags 0x%x error %d", dmat, dmat->flags, ENOMEM); 501 return (ENOMEM); 502 } 503 } 504 505 if ((dmat->maxsize <= PAGE_SIZE) && 506 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 507 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 508 } else { 509 /* 510 * XXX Use Contigmalloc until it is merged into this facility 511 * and handles multi-seg allocations. Nobody is doing 512 * multi-seg allocations yet though. 513 * XXX Certain AGP hardware does. 514 */ 515 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 516 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 517 dmat->boundary); 518 } 519 if (*vaddr == NULL) { 520 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag flags 0x%x " 521 "error %d", dmat, dmat->flags, ENOMEM); 522 return (ENOMEM); 523 } 524 CTR3(KTR_BUSDMA, "bus_dmamem_alloc: tag %p tag flags 0x%x error %d", 525 dmat, dmat->flags, ENOMEM); 526 return (0); 527} 528 529/* 530 * Free a piece of memory and it's allociated dmamap, that was allocated 531 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 532 */ 533void 534bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 535{ 536 /* 537 * dmamem does not need to be bounced, so the map should be 538 * NULL 539 */ 540 if (map != NULL) 541 panic("bus_dmamem_free: Invalid map freed\n"); 542 if ((dmat->maxsize <= PAGE_SIZE) 543 && dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 544 free(vaddr, M_DEVBUF); 545 else { 546 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 547 } 548 CTR2(KTR_BUSDMA, "bus_dmamem_free: tag %p flags 0x%x", dmat, 549 dmat->flags); 550} 551 552/* 553 * Utility function to load a linear buffer. lastaddrp holds state 554 * between invocations (for multiple-buffer loads). segp contains 555 * the starting segment on entrace, and the ending segment on exit. 556 * first indicates if this is the first invocation of this function. 557 */ 558static __inline int 559_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 560 bus_dmamap_t map, 561 void *buf, bus_size_t buflen, 562 pmap_t pmap, 563 int flags, 564 bus_addr_t *lastaddrp, 565 bus_dma_segment_t *segs, 566 int *segp, 567 int first) 568{ 569 bus_size_t sgsize; 570 bus_addr_t curaddr, lastaddr, baddr, bmask; 571 vm_offset_t vaddr; 572 bus_addr_t paddr; 573 int needbounce = 0; 574 int seg; 575 576 if (map == NULL) 577 map = &nobounce_dmamap; 578 579 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 580 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 581 vm_offset_t vendaddr; 582 583 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 584 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 585 dmat->boundary, dmat->alignment); 586 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 587 map, &nobounce_dmamap, map->pagesneeded); 588 /* 589 * Count the number of bounce pages 590 * needed in order to complete this transfer 591 */ 592 vaddr = trunc_page((vm_offset_t)buf); 593 vendaddr = (vm_offset_t)buf + buflen; 594 595 while (vaddr < vendaddr) { 596 paddr = pmap_kextract(vaddr); 597 if (run_filter(dmat, paddr) != 0) { 598 needbounce = 1; 599 map->pagesneeded++; 600 } 601 vaddr += PAGE_SIZE; 602 } 603 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 604 } 605 606 /* Reserve Necessary Bounce Pages */ 607 if (map->pagesneeded != 0) { 608 mtx_lock(&bounce_lock); 609 if (flags & BUS_DMA_NOWAIT) { 610 if (reserve_bounce_pages(dmat, map, 0) != 0) { 611 mtx_unlock(&bounce_lock); 612 return (ENOMEM); 613 } 614 } else { 615 if (reserve_bounce_pages(dmat, map, 1) != 0) { 616 /* Queue us for resources */ 617 map->dmat = dmat; 618 map->buf = buf; 619 map->buflen = buflen; 620 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 621 map, links); 622 mtx_unlock(&bounce_lock); 623 return (EINPROGRESS); 624 } 625 } 626 mtx_unlock(&bounce_lock); 627 } 628 629 vaddr = (vm_offset_t)buf; 630 lastaddr = *lastaddrp; 631 bmask = ~(dmat->boundary - 1); 632 633 for (seg = *segp; buflen > 0 ; ) { 634 /* 635 * Get the physical address for this segment. 636 */ 637 if (pmap) 638 curaddr = pmap_extract(pmap, vaddr); 639 else 640 curaddr = pmap_kextract(vaddr); 641 642 /* 643 * Compute the segment size, and adjust counts. 644 */ 645 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 646 if (buflen < sgsize) 647 sgsize = buflen; 648 649 /* 650 * Make sure we don't cross any boundaries. 651 */ 652 if (dmat->boundary > 0) { 653 baddr = (curaddr + dmat->boundary) & bmask; 654 if (sgsize > (baddr - curaddr)) 655 sgsize = (baddr - curaddr); 656 } 657 658 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) 659 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 660 661 /* 662 * Insert chunk into a segment, coalescing with 663 * previous segment if possible. 664 */ 665 if (first) { 666 segs[seg].ds_addr = curaddr; 667 segs[seg].ds_len = sgsize; 668 first = 0; 669 } else { 670 if (needbounce == 0 && curaddr == lastaddr && 671 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 672 (dmat->boundary == 0 || 673 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 674 segs[seg].ds_len += sgsize; 675 else { 676 if (++seg >= dmat->nsegments) 677 break; 678 segs[seg].ds_addr = curaddr; 679 segs[seg].ds_len = sgsize; 680 } 681 } 682 683 lastaddr = curaddr + sgsize; 684 vaddr += sgsize; 685 buflen -= sgsize; 686 } 687 688 *segp = seg; 689 *lastaddrp = lastaddr; 690 691 /* 692 * Did we fit? 693 */ 694 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 695} 696 697/* 698 * Map the buffer buf into bus space using the dmamap map. 699 */ 700int 701bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 702 bus_size_t buflen, bus_dmamap_callback_t *callback, 703 void *callback_arg, int flags) 704{ 705 bus_addr_t lastaddr = 0; 706 int error, nsegs = 0; 707 708 if (map != NULL) { 709 flags |= BUS_DMA_WAITOK; 710 map->callback = callback; 711 map->callback_arg = callback_arg; 712 } 713 714 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 715 &lastaddr, dmat->segments, &nsegs, 1); 716 717 if (error == EINPROGRESS) { 718 CTR3(KTR_BUSDMA, "bus_dmamap_load: tag %p tag flags 0x%x " 719 "error %d", dmat, dmat->flags, error); 720 return (error); 721 } 722 723 if (error) 724 (*callback)(callback_arg, dmat->segments, 0, error); 725 else 726 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 727 728 CTR3(KTR_BUSDMA, "bus_dmamap_load: tag %p tag flags 0x%x error 0 " 729 "nsegs %d", dmat, dmat->flags, nsegs + 1); 730 return (0); 731} 732 733 734/* 735 * Like _bus_dmamap_load(), but for mbufs. 736 */ 737int 738bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 739 struct mbuf *m0, 740 bus_dmamap_callback2_t *callback, void *callback_arg, 741 int flags) 742{ 743 int nsegs, error; 744 745 M_ASSERTPKTHDR(m0); 746 747 flags |= BUS_DMA_NOWAIT; 748 nsegs = 0; 749 error = 0; 750 if (m0->m_pkthdr.len <= dmat->maxsize) { 751 int first = 1; 752 bus_addr_t lastaddr = 0; 753 struct mbuf *m; 754 755 for (m = m0; m != NULL && error == 0; m = m->m_next) { 756 if (m->m_len > 0) { 757 error = _bus_dmamap_load_buffer(dmat, map, 758 m->m_data, m->m_len, 759 NULL, flags, &lastaddr, 760 dmat->segments, &nsegs, first); 761 first = 0; 762 } 763 } 764 } else { 765 error = EINVAL; 766 } 767 768 if (error) { 769 /* force "no valid mappings" in callback */ 770 (*callback)(callback_arg, dmat->segments, 0, 0, error); 771 } else { 772 (*callback)(callback_arg, dmat->segments, 773 nsegs+1, m0->m_pkthdr.len, error); 774 } 775 CTR4(KTR_BUSDMA, "bus_dmamap_load_mbuf: tag %p tag flags 0x%x " 776 "error %d nsegs %d", dmat, dmat->flags, error, nsegs + 1); 777 return (error); 778} 779 780int 781bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 782 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 783 int flags) 784{ 785 int error; 786 787 M_ASSERTPKTHDR(m0); 788 789 flags |= BUS_DMA_NOWAIT; 790 *nsegs = 0; 791 error = 0; 792 if (m0->m_pkthdr.len <= dmat->maxsize) { 793 int first = 1; 794 bus_addr_t lastaddr = 0; 795 struct mbuf *m; 796 797 for (m = m0; m != NULL && error == 0; m = m->m_next) { 798 if (m->m_len > 0) { 799 error = _bus_dmamap_load_buffer(dmat, map, 800 m->m_data, m->m_len, 801 NULL, flags, &lastaddr, 802 segs, nsegs, first); 803 first = 0; 804 } 805 } 806 } else { 807 error = EINVAL; 808 } 809 810 /* XXX FIXME: Having to increment nsegs is really annoying */ 811 ++*nsegs; 812 CTR4(KTR_BUSDMA, "bus_dmamap_load_mbuf: tag %p tag flags 0x%x " 813 "error %d nsegs %d", dmat, dmat->flags, error, *nsegs); 814 return (error); 815} 816 817/* 818 * Like _bus_dmamap_load(), but for uios. 819 */ 820int 821bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 822 struct uio *uio, 823 bus_dmamap_callback2_t *callback, void *callback_arg, 824 int flags) 825{ 826 bus_addr_t lastaddr; 827 int nsegs, error, first, i; 828 bus_size_t resid; 829 struct iovec *iov; 830 pmap_t pmap; 831 832 flags |= BUS_DMA_NOWAIT; 833 resid = uio->uio_resid; 834 iov = uio->uio_iov; 835 836 if (uio->uio_segflg == UIO_USERSPACE) { 837 KASSERT(uio->uio_td != NULL, 838 ("bus_dmamap_load_uio: USERSPACE but no proc")); 839 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 840 } else 841 pmap = NULL; 842 843 nsegs = 0; 844 error = 0; 845 first = 1; 846 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 847 /* 848 * Now at the first iovec to load. Load each iovec 849 * until we have exhausted the residual count. 850 */ 851 bus_size_t minlen = 852 resid < iov[i].iov_len ? resid : iov[i].iov_len; 853 caddr_t addr = (caddr_t) iov[i].iov_base; 854 855 if (minlen > 0) { 856 error = _bus_dmamap_load_buffer(dmat, map, 857 addr, minlen, pmap, flags, &lastaddr, 858 dmat->segments, &nsegs, first); 859 first = 0; 860 861 resid -= minlen; 862 } 863 } 864 865 if (error) { 866 /* force "no valid mappings" in callback */ 867 (*callback)(callback_arg, dmat->segments, 0, 0, error); 868 } else { 869 (*callback)(callback_arg, dmat->segments, 870 nsegs+1, uio->uio_resid, error); 871 } 872 CTR4(KTR_BUSDMA, "bus_dmamap_load_uio: tag %p tag flags 0x%x " 873 "error %d nsegs %d", dmat, dmat->flags, error, nsegs + 1); 874 return (error); 875} 876 877/* 878 * Release the mapping held by map. 879 */ 880void 881_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 882{ 883 struct bounce_page *bpage; 884 885 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 886 STAILQ_REMOVE_HEAD(&map->bpages, links); 887 free_bounce_page(dmat, bpage); 888 } 889} 890 891void 892_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 893{ 894 struct bounce_page *bpage; 895 896 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 897 /* 898 * Handle data bouncing. We might also 899 * want to add support for invalidating 900 * the caches on broken hardware 901 */ 902 dmat->bounce_zone->total_bounced++; 903 CTR3(KTR_BUSDMA, "_bus_dmamap_sync: tag %p tag flags 0x%x " 904 "op 0x%x performing bounce", op, dmat, dmat->flags); 905 906 if (op & BUS_DMASYNC_PREWRITE) { 907 while (bpage != NULL) { 908 bcopy((void *)bpage->datavaddr, 909 (void *)bpage->vaddr, 910 bpage->datacount); 911 bpage = STAILQ_NEXT(bpage, links); 912 } 913 } 914 915 if (op & BUS_DMASYNC_POSTREAD) { 916 while (bpage != NULL) { 917 bcopy((void *)bpage->vaddr, 918 (void *)bpage->datavaddr, 919 bpage->datacount); 920 bpage = STAILQ_NEXT(bpage, links); 921 } 922 } 923 } 924} 925 926static void 927init_bounce_pages(void *dummy __unused) 928{ 929 930 total_bpages = 0; 931 STAILQ_INIT(&bounce_zone_list); 932 STAILQ_INIT(&bounce_map_waitinglist); 933 STAILQ_INIT(&bounce_map_callbacklist); 934 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 935} 936SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 937 938static struct sysctl_ctx_list * 939busdma_sysctl_tree(struct bounce_zone *bz) 940{ 941 return (&bz->sysctl_tree); 942} 943 944static struct sysctl_oid * 945busdma_sysctl_tree_top(struct bounce_zone *bz) 946{ 947 return (bz->sysctl_tree_top); 948} 949 950static int 951alloc_bounce_zone(bus_dma_tag_t dmat) 952{ 953 struct bounce_zone *bz; 954 955 /* Check to see if we already have a suitable zone */ 956 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 957 if ((dmat->alignment <= bz->alignment) 958 && (dmat->boundary <= bz->boundary) 959 && (dmat->lowaddr >= bz->lowaddr)) { 960 dmat->bounce_zone = bz; 961 return (0); 962 } 963 } 964 965 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 966 M_NOWAIT | M_ZERO)) == NULL) 967 return (ENOMEM); 968 969 STAILQ_INIT(&bz->bounce_page_list); 970 bz->free_bpages = 0; 971 bz->reserved_bpages = 0; 972 bz->active_bpages = 0; 973 bz->lowaddr = dmat->lowaddr; 974 bz->alignment = dmat->alignment; 975 bz->boundary = dmat->boundary; 976 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 977 busdma_zonecount++; 978 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 979 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 980 dmat->bounce_zone = bz; 981 982 sysctl_ctx_init(&bz->sysctl_tree); 983 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 984 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 985 CTLFLAG_RD, 0, ""); 986 if (bz->sysctl_tree_top == NULL) { 987 sysctl_ctx_free(&bz->sysctl_tree); 988 return (0); /* XXX error code? */ 989 } 990 991 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 992 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 993 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 994 "Totoal bounce pages"); 995 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 996 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 997 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 998 "Free bounce pages"); 999 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1000 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1001 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1002 "Reserved bounce pages"); 1003 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1004 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1005 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1006 "Active bounce pages"); 1007 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1008 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1009 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1010 "Total bounce requests"); 1011 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1012 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1013 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1014 "Total bounce requests that were deferred"); 1015 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1016 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1017 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1020 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1021 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1022 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1023 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 1024 1025 return (0); 1026} 1027 1028static int 1029alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1030{ 1031 struct bounce_zone *bz; 1032 int count; 1033 1034 bz = dmat->bounce_zone; 1035 count = 0; 1036 while (numpages > 0) { 1037 struct bounce_page *bpage; 1038 1039 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1040 M_NOWAIT | M_ZERO); 1041 1042 if (bpage == NULL) 1043 break; 1044 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1045 M_NOWAIT, 0ul, 1046 bz->lowaddr, 1047 PAGE_SIZE, 1048 bz->boundary); 1049 if (bpage->vaddr == 0) { 1050 free(bpage, M_DEVBUF); 1051 break; 1052 } 1053 bpage->busaddr = pmap_kextract(bpage->vaddr); 1054 mtx_lock(&bounce_lock); 1055 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1056 total_bpages++; 1057 bz->total_bpages++; 1058 bz->free_bpages++; 1059 mtx_unlock(&bounce_lock); 1060 count++; 1061 numpages--; 1062 } 1063 return (count); 1064} 1065 1066static int 1067reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1068{ 1069 struct bounce_zone *bz; 1070 int pages; 1071 1072 mtx_assert(&bounce_lock, MA_OWNED); 1073 bz = dmat->bounce_zone; 1074 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1075 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1076 return (map->pagesneeded - (map->pagesreserved + pages)); 1077 bz->free_bpages -= pages; 1078 bz->reserved_bpages += pages; 1079 map->pagesreserved += pages; 1080 pages = map->pagesneeded - map->pagesreserved; 1081 1082 return (pages); 1083} 1084 1085static bus_addr_t 1086add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1087 bus_size_t size) 1088{ 1089 struct bounce_zone *bz; 1090 struct bounce_page *bpage; 1091 1092 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1093 KASSERT(map != NULL && map != &nobounce_dmamap, 1094 ("add_bounce_page: bad map %p", map)); 1095 1096 bz = dmat->bounce_zone; 1097 if (map->pagesneeded == 0) 1098 panic("add_bounce_page: map doesn't need any pages"); 1099 map->pagesneeded--; 1100 1101 if (map->pagesreserved == 0) 1102 panic("add_bounce_page: map doesn't need any pages"); 1103 map->pagesreserved--; 1104 1105 mtx_lock(&bounce_lock); 1106 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1107 if (bpage == NULL) 1108 panic("add_bounce_page: free page list is empty"); 1109 1110 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1111 bz->reserved_bpages--; 1112 bz->active_bpages++; 1113 mtx_unlock(&bounce_lock); 1114 1115 bpage->datavaddr = vaddr; 1116 bpage->datacount = size; 1117 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1118 return (bpage->busaddr); 1119} 1120 1121static void 1122free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1123{ 1124 struct bus_dmamap *map; 1125 struct bounce_zone *bz; 1126 1127 bz = dmat->bounce_zone; 1128 bpage->datavaddr = 0; 1129 bpage->datacount = 0; 1130 1131 mtx_lock(&bounce_lock); 1132 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1133 bz->free_bpages++; 1134 bz->active_bpages--; 1135 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1136 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1137 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1138 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1139 map, links); 1140 busdma_swi_pending = 1; 1141 bz->total_deferred++; 1142 swi_sched(vm_ih, 0); 1143 } 1144 } 1145 mtx_unlock(&bounce_lock); 1146} 1147 1148void 1149busdma_swi(void) 1150{ 1151 bus_dma_tag_t dmat; 1152 struct bus_dmamap *map; 1153 1154 mtx_lock(&bounce_lock); 1155 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1156 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1157 mtx_unlock(&bounce_lock); 1158 dmat = map->dmat; 1159 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1160 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1161 map->callback, map->callback_arg, /*flags*/0); 1162 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1163 mtx_lock(&bounce_lock); 1164 } 1165 mtx_unlock(&bounce_lock); 1166} 1167