busdma_machdep.c revision 162275
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 162275 2006-09-13 09:35:59Z scottl $"); 29 30#include <sys/param.h> 31#include <sys/kdb.h> 32#include <ddb/ddb.h> 33#include <ddb/db_output.h> 34#include <sys/systm.h> 35#include <sys/malloc.h> 36#include <sys/bus.h> 37#include <sys/interrupt.h> 38#include <sys/kernel.h> 39#include <sys/ktr.h> 40#include <sys/lock.h> 41#include <sys/proc.h> 42#include <sys/mutex.h> 43#include <sys/mbuf.h> 44#include <sys/uio.h> 45#include <sys/sysctl.h> 46 47#include <vm/vm.h> 48#include <vm/vm_page.h> 49#include <vm/vm_map.h> 50 51#include <machine/atomic.h> 52#include <machine/bus.h> 53#include <machine/md_var.h> 54 55#define MAX_BPAGES 512 56#define BUS_DMA_USE_FILTER BUS_DMA_BUS2 57#define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 58#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 59 60struct bounce_zone; 61 62struct bus_dma_tag { 63 bus_dma_tag_t parent; 64 bus_size_t alignment; 65 bus_size_t boundary; 66 bus_addr_t lowaddr; 67 bus_addr_t highaddr; 68 bus_dma_filter_t *filter; 69 void *filterarg; 70 bus_size_t maxsize; 71 u_int nsegments; 72 bus_size_t maxsegsz; 73 int flags; 74 int ref_count; 75 int map_count; 76 bus_dma_lock_t *lockfunc; 77 void *lockfuncarg; 78 bus_dma_segment_t *segments; 79 struct bounce_zone *bounce_zone; 80}; 81 82struct bounce_page { 83 vm_offset_t vaddr; /* kva of bounce buffer */ 84 bus_addr_t busaddr; /* Physical address */ 85 vm_offset_t datavaddr; /* kva of client data */ 86 bus_size_t datacount; /* client data count */ 87 STAILQ_ENTRY(bounce_page) links; 88}; 89 90int busdma_swi_pending; 91 92struct bounce_zone { 93 STAILQ_ENTRY(bounce_zone) links; 94 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 95 int total_bpages; 96 int free_bpages; 97 int reserved_bpages; 98 int active_bpages; 99 int total_bounced; 100 int total_deferred; 101 bus_size_t alignment; 102 bus_size_t boundary; 103 bus_addr_t lowaddr; 104 char zoneid[8]; 105 char lowaddrid[20]; 106 struct sysctl_ctx_list sysctl_tree; 107 struct sysctl_oid *sysctl_tree_top; 108}; 109 110static struct mtx bounce_lock; 111static int total_bpages; 112static int busdma_zonecount; 113static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 114 115SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 116SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 117 "Total bounce pages"); 118 119struct bus_dmamap { 120 struct bp_list bpages; 121 int pagesneeded; 122 int pagesreserved; 123 bus_dma_tag_t dmat; 124 void *buf; /* unmapped buffer pointer */ 125 bus_size_t buflen; /* unmapped buffer length */ 126 bus_dmamap_callback_t *callback; 127 void *callback_arg; 128 STAILQ_ENTRY(bus_dmamap) links; 129}; 130 131static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 132static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 133static struct bus_dmamap nobounce_dmamap; 134 135static void init_bounce_pages(void *dummy); 136static int alloc_bounce_zone(bus_dma_tag_t dmat); 137static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 138static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 139 int commit); 140static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 141 vm_offset_t vaddr, bus_size_t size); 142static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 143int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 144int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 145 bus_size_t buflen, int flags, int *nb); 146 147/* 148 * Return true if a match is made. 149 * 150 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 151 * 152 * If paddr is within the bounds of the dma tag then call the filter callback 153 * to check for a match, if there is no filter callback then assume a match. 154 */ 155int 156run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 157{ 158 int retval; 159 160 retval = 0; 161 162 do { 163 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 164 || ((paddr & (dmat->alignment - 1)) != 0)) 165 && (dmat->filter == NULL 166 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 167 retval = 1; 168 169 dmat = dmat->parent; 170 } while (retval == 0 && dmat != NULL); 171 return (retval); 172} 173 174/* 175 * Convenience function for manipulating driver locks from busdma (during 176 * busdma_swi, for example). Drivers that don't provide their own locks 177 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 178 * non-mutex locking scheme don't have to use this at all. 179 */ 180void 181busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 182{ 183 struct mtx *dmtx; 184 185 dmtx = (struct mtx *)arg; 186 switch (op) { 187 case BUS_DMA_LOCK: 188 mtx_lock(dmtx); 189 break; 190 case BUS_DMA_UNLOCK: 191 mtx_unlock(dmtx); 192 break; 193 default: 194 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 195 } 196} 197 198/* 199 * dflt_lock should never get called. It gets put into the dma tag when 200 * lockfunc == NULL, which is only valid if the maps that are associated 201 * with the tag are meant to never be defered. 202 * XXX Should have a way to identify which driver is responsible here. 203 */ 204static void 205dflt_lock(void *arg, bus_dma_lock_op_t op) 206{ 207 panic("driver error: busdma dflt_lock called"); 208} 209 210/* 211 * Allocate a device specific dma_tag. 212 */ 213int 214bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 215 bus_size_t boundary, bus_addr_t lowaddr, 216 bus_addr_t highaddr, bus_dma_filter_t *filter, 217 void *filterarg, bus_size_t maxsize, int nsegments, 218 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 219 void *lockfuncarg, bus_dma_tag_t *dmat) 220{ 221 bus_dma_tag_t newtag; 222 int error = 0; 223 224 /* Basic sanity checking */ 225 if (boundary != 0 && boundary < maxsegsz) 226 maxsegsz = boundary; 227 228 /* Return a NULL tag on failure */ 229 *dmat = NULL; 230 231 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 232 M_ZERO | M_NOWAIT); 233 if (newtag == NULL) { 234 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 235 __func__, newtag, 0, error); 236 return (ENOMEM); 237 } 238 239 newtag->parent = parent; 240 newtag->alignment = alignment; 241 newtag->boundary = boundary; 242 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 243 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 244 (PAGE_SIZE - 1); 245 newtag->filter = filter; 246 newtag->filterarg = filterarg; 247 newtag->maxsize = maxsize; 248 newtag->nsegments = nsegments; 249 newtag->maxsegsz = maxsegsz; 250 newtag->flags = flags; 251 newtag->ref_count = 1; /* Count ourself */ 252 newtag->map_count = 0; 253 if (lockfunc != NULL) { 254 newtag->lockfunc = lockfunc; 255 newtag->lockfuncarg = lockfuncarg; 256 } else { 257 newtag->lockfunc = dflt_lock; 258 newtag->lockfuncarg = NULL; 259 } 260 newtag->segments = NULL; 261 262 /* Take into account any restrictions imposed by our parent tag */ 263 if (parent != NULL) { 264 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 265 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 266 if (newtag->boundary == 0) 267 newtag->boundary = parent->boundary; 268 else if (parent->boundary != 0) 269 newtag->boundary = MIN(parent->boundary, 270 newtag->boundary); 271 if ((newtag->filter != NULL) || 272 ((parent->flags & BUS_DMA_USE_FILTER) != 0)) 273 newtag->flags |= BUS_DMA_USE_FILTER; 274 if (newtag->filter == NULL) { 275 /* 276 * Short circuit looking at our parent directly 277 * since we have encapsulated all of its information 278 */ 279 newtag->filter = parent->filter; 280 newtag->filterarg = parent->filterarg; 281 newtag->parent = parent->parent; 282 } 283 if (newtag->parent != NULL) 284 atomic_add_int(&parent->ref_count, 1); 285 } 286 287 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 288 || newtag->alignment > 1) 289 newtag->flags |= BUS_DMA_COULD_BOUNCE; 290 291 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 292 (flags & BUS_DMA_ALLOCNOW) != 0) { 293 struct bounce_zone *bz; 294 295 /* Must bounce */ 296 297 if ((error = alloc_bounce_zone(newtag)) != 0) { 298 free(newtag, M_DEVBUF); 299 return (error); 300 } 301 bz = newtag->bounce_zone; 302 303 if (ptoa(bz->total_bpages) < maxsize) { 304 int pages; 305 306 pages = atop(maxsize) - bz->total_bpages; 307 308 /* Add pages to our bounce pool */ 309 if (alloc_bounce_pages(newtag, pages) < pages) 310 error = ENOMEM; 311 } 312 /* Performed initial allocation */ 313 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 314 } 315 316 if (error != 0) { 317 free(newtag, M_DEVBUF); 318 } else { 319 *dmat = newtag; 320 } 321 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 322 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 323 return (error); 324} 325 326int 327bus_dma_tag_destroy(bus_dma_tag_t dmat) 328{ 329 bus_dma_tag_t dmat_copy; 330 int error; 331 332 error = 0; 333 dmat_copy = dmat; 334 335 if (dmat != NULL) { 336 337 if (dmat->map_count != 0) { 338 error = EBUSY; 339 goto out; 340 } 341 342 while (dmat != NULL) { 343 bus_dma_tag_t parent; 344 345 parent = dmat->parent; 346 atomic_subtract_int(&dmat->ref_count, 1); 347 if (dmat->ref_count == 0) { 348 if (dmat->segments != NULL) 349 free(dmat->segments, M_DEVBUF); 350 free(dmat, M_DEVBUF); 351 /* 352 * Last reference count, so 353 * release our reference 354 * count on our parent. 355 */ 356 dmat = parent; 357 } else 358 dmat = NULL; 359 } 360 } 361out: 362 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 363 return (error); 364} 365 366/* 367 * Allocate a handle for mapping from kva/uva/physical 368 * address space into bus device space. 369 */ 370int 371bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 372{ 373 int error; 374 375 error = 0; 376 377 if (dmat->segments == NULL) { 378 dmat->segments = (bus_dma_segment_t *)malloc( 379 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 380 M_NOWAIT); 381 if (dmat->segments == NULL) { 382 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 383 __func__, dmat, ENOMEM); 384 return (ENOMEM); 385 } 386 } 387 388 /* 389 * Bouncing might be required if the driver asks for an active 390 * exclusion region, a data alignment that is stricter than 1, and/or 391 * an active address boundary. 392 */ 393 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 394 395 /* Must bounce */ 396 struct bounce_zone *bz; 397 int maxpages; 398 399 if (dmat->bounce_zone == NULL) { 400 if ((error = alloc_bounce_zone(dmat)) != 0) 401 return (error); 402 } 403 bz = dmat->bounce_zone; 404 405 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 406 M_NOWAIT | M_ZERO); 407 if (*mapp == NULL) { 408 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 409 __func__, dmat, ENOMEM); 410 return (ENOMEM); 411 } 412 413 /* Initialize the new map */ 414 STAILQ_INIT(&((*mapp)->bpages)); 415 416 /* 417 * Attempt to add pages to our pool on a per-instance 418 * basis up to a sane limit. 419 */ 420 if (dmat->alignment > 1) 421 maxpages = MAX_BPAGES; 422 else 423 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 424 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 425 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 426 int pages; 427 428 pages = MAX(atop(dmat->maxsize), 1); 429 pages = MIN(maxpages - bz->total_bpages, pages); 430 pages = MAX(pages, 1); 431 if (alloc_bounce_pages(dmat, pages) < pages) 432 error = ENOMEM; 433 434 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 435 if (error == 0) 436 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 437 } else { 438 error = 0; 439 } 440 } 441 } else { 442 *mapp = NULL; 443 } 444 if (error == 0) 445 dmat->map_count++; 446 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 447 __func__, dmat, dmat->flags, error); 448 return (error); 449} 450 451/* 452 * Destroy a handle for mapping from kva/uva/physical 453 * address space into bus device space. 454 */ 455int 456bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 457{ 458 if (map != NULL && map != &nobounce_dmamap) { 459 if (STAILQ_FIRST(&map->bpages) != NULL) { 460 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 461 __func__, dmat, EBUSY); 462 return (EBUSY); 463 } 464 free(map, M_DEVBUF); 465 } 466 dmat->map_count--; 467 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 468 return (0); 469} 470 471 472/* 473 * Allocate a piece of memory that can be efficiently mapped into 474 * bus device space based on the constraints lited in the dma tag. 475 * A dmamap to for use with dmamap_load is also allocated. 476 */ 477int 478bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 479 bus_dmamap_t *mapp) 480{ 481 int mflags; 482 483 if (flags & BUS_DMA_NOWAIT) 484 mflags = M_NOWAIT; 485 else 486 mflags = M_WAITOK; 487 if (flags & BUS_DMA_ZERO) 488 mflags |= M_ZERO; 489 490 /* If we succeed, no mapping/bouncing will be required */ 491 *mapp = NULL; 492 493 if (dmat->segments == NULL) { 494 dmat->segments = (bus_dma_segment_t *)malloc( 495 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 496 M_NOWAIT); 497 if (dmat->segments == NULL) { 498 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 499 __func__, dmat, dmat->flags, ENOMEM); 500 return (ENOMEM); 501 } 502 } 503 504 /* 505 * XXX: 506 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 507 * alignment guarantees of malloc need to be nailed down, and the 508 * code below should be rewritten to take that into account. 509 * 510 * In the meantime, we'll warn the user if malloc gets it wrong. 511 */ 512 if ((dmat->maxsize <= PAGE_SIZE) && 513 (dmat->alignment < dmat->maxsize) && 514 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 515 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 516 } else { 517 /* 518 * XXX Use Contigmalloc until it is merged into this facility 519 * and handles multi-seg allocations. Nobody is doing 520 * multi-seg allocations yet though. 521 * XXX Certain AGP hardware does. 522 */ 523 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 524 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 525 dmat->boundary); 526 } 527 if (*vaddr == NULL) { 528 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 529 __func__, dmat, dmat->flags, ENOMEM); 530 return (ENOMEM); 531 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 532 printf("bus_dmamem_alloc failed to align memory properly."); 533 } 534 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 535 __func__, dmat, dmat->flags, ENOMEM); 536 return (0); 537} 538 539/* 540 * Free a piece of memory and it's allociated dmamap, that was allocated 541 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 542 */ 543void 544bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 545{ 546 /* 547 * dmamem does not need to be bounced, so the map should be 548 * NULL 549 */ 550 if (map != NULL) 551 panic("bus_dmamem_free: Invalid map freed\n"); 552 if ((dmat->maxsize <= PAGE_SIZE) && 553 (dmat->alignment < dmat->maxsize) && 554 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 555 free(vaddr, M_DEVBUF); 556 else { 557 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 558 } 559 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 560} 561 562int 563_bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 564 bus_size_t buflen, int flags, int *nb) 565{ 566 vm_offset_t vaddr; 567 vm_offset_t vendaddr; 568 bus_addr_t paddr; 569 int needbounce = *nb; 570 571 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 572 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 573 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 574 dmat->boundary, dmat->alignment); 575 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 576 map, &nobounce_dmamap, map->pagesneeded); 577 /* 578 * Count the number of bounce pages 579 * needed in order to complete this transfer 580 */ 581 vaddr = trunc_page((vm_offset_t)buf); 582 vendaddr = (vm_offset_t)buf + buflen; 583 584 while (vaddr < vendaddr) { 585 paddr = pmap_kextract(vaddr); 586 if (((dmat->flags & BUS_DMA_USE_FILTER) != 0) && 587 run_filter(dmat, paddr) != 0) { 588 needbounce = 1; 589 map->pagesneeded++; 590 } 591 vaddr += PAGE_SIZE; 592 } 593 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 594 } 595 596 /* Reserve Necessary Bounce Pages */ 597 if (map->pagesneeded != 0) { 598 mtx_lock(&bounce_lock); 599 if (flags & BUS_DMA_NOWAIT) { 600 if (reserve_bounce_pages(dmat, map, 0) != 0) { 601 mtx_unlock(&bounce_lock); 602 return (ENOMEM); 603 } 604 } else { 605 if (reserve_bounce_pages(dmat, map, 1) != 0) { 606 /* Queue us for resources */ 607 map->dmat = dmat; 608 map->buf = buf; 609 map->buflen = buflen; 610 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 611 map, links); 612 mtx_unlock(&bounce_lock); 613 return (EINPROGRESS); 614 } 615 } 616 mtx_unlock(&bounce_lock); 617 } 618 619 *nb = needbounce; 620 return (0); 621} 622 623/* 624 * Utility function to load a linear buffer. lastaddrp holds state 625 * between invocations (for multiple-buffer loads). segp contains 626 * the starting segment on entrace, and the ending segment on exit. 627 * first indicates if this is the first invocation of this function. 628 */ 629static __inline int 630_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 631 bus_dmamap_t map, 632 void *buf, bus_size_t buflen, 633 pmap_t pmap, 634 int flags, 635 bus_addr_t *lastaddrp, 636 bus_dma_segment_t *segs, 637 int *segp, 638 int first) 639{ 640 bus_size_t sgsize; 641 bus_addr_t curaddr, lastaddr, baddr, bmask; 642 vm_offset_t vaddr; 643 int needbounce = 0; 644 int seg, error; 645 646 if (map == NULL) 647 map = &nobounce_dmamap; 648 649 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) { 650 error = _bus_dmamap_count_pages(dmat, map, buf, buflen, flags, 651 &needbounce); 652 if (error) 653 return (error); 654 } 655 656 vaddr = (vm_offset_t)buf; 657 lastaddr = *lastaddrp; 658 bmask = ~(dmat->boundary - 1); 659 660 for (seg = *segp; buflen > 0 ; ) { 661 /* 662 * Get the physical address for this segment. 663 */ 664 if (pmap) 665 curaddr = pmap_extract(pmap, vaddr); 666 else 667 curaddr = pmap_kextract(vaddr); 668 669 /* 670 * Compute the segment size, and adjust counts. 671 */ 672 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 673 if (buflen < sgsize) 674 sgsize = buflen; 675 676 /* 677 * Make sure we don't cross any boundaries. 678 */ 679 if (dmat->boundary > 0) { 680 baddr = (curaddr + dmat->boundary) & bmask; 681 if (sgsize > (baddr - curaddr)) 682 sgsize = (baddr - curaddr); 683 } 684 685 if (((dmat->flags & BUS_DMA_USE_FILTER) != 0) && 686 map->pagesneeded != 0 && run_filter(dmat, curaddr)) 687 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 688 689 /* 690 * Insert chunk into a segment, coalescing with 691 * previous segment if possible. 692 */ 693 if (first) { 694 segs[seg].ds_addr = curaddr; 695 segs[seg].ds_len = sgsize; 696 first = 0; 697 } else { 698 if (needbounce == 0 && curaddr == lastaddr && 699 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 700 (dmat->boundary == 0 || 701 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 702 segs[seg].ds_len += sgsize; 703 else { 704 if (++seg >= dmat->nsegments) 705 break; 706 segs[seg].ds_addr = curaddr; 707 segs[seg].ds_len = sgsize; 708 } 709 } 710 711 lastaddr = curaddr + sgsize; 712 vaddr += sgsize; 713 buflen -= sgsize; 714 } 715 716 *segp = seg; 717 *lastaddrp = lastaddr; 718 719 /* 720 * Did we fit? 721 */ 722 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 723} 724 725/* 726 * Map the buffer buf into bus space using the dmamap map. 727 */ 728int 729bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 730 bus_size_t buflen, bus_dmamap_callback_t *callback, 731 void *callback_arg, int flags) 732{ 733 bus_addr_t lastaddr = 0; 734 int error, nsegs = 0; 735 736 if (map != NULL) { 737 flags |= BUS_DMA_WAITOK; 738 map->callback = callback; 739 map->callback_arg = callback_arg; 740 } 741 742 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 743 &lastaddr, dmat->segments, &nsegs, 1); 744 745 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 746 __func__, dmat, dmat->flags, error, nsegs + 1); 747 748 if (error == EINPROGRESS) { 749 return (error); 750 } 751 752 if (error) 753 (*callback)(callback_arg, dmat->segments, 0, error); 754 else 755 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 756 757 /* 758 * Return ENOMEM to the caller so that it can pass it up the stack. 759 * This error only happens when NOWAIT is set, so deferal is disabled. 760 */ 761 if (error == ENOMEM) 762 return (error); 763 764 return (0); 765} 766 767 768/* 769 * Like _bus_dmamap_load(), but for mbufs. 770 */ 771static __inline int 772_bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 773 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 774 int flags) 775{ 776 int error; 777 778 M_ASSERTPKTHDR(m0); 779 780 flags |= BUS_DMA_NOWAIT; 781 *nsegs = 0; 782 error = 0; 783 if (m0->m_pkthdr.len <= dmat->maxsize) { 784 int first = 1; 785 bus_addr_t lastaddr = 0; 786 struct mbuf *m; 787 788 for (m = m0; m != NULL && error == 0; m = m->m_next) { 789 if (m->m_len > 0) { 790 error = _bus_dmamap_load_buffer(dmat, map, 791 m->m_data, m->m_len, 792 NULL, flags, &lastaddr, 793 segs, nsegs, first); 794 first = 0; 795 } 796 } 797 } else { 798 error = EINVAL; 799 } 800 801 /* XXX FIXME: Having to increment nsegs is really annoying */ 802 ++*nsegs; 803 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 804 __func__, dmat, dmat->flags, error, *nsegs); 805 return (error); 806} 807 808int 809bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 810 struct mbuf *m0, 811 bus_dmamap_callback2_t *callback, void *callback_arg, 812 int flags) 813{ 814 int nsegs, error; 815 816 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs, 817 flags); 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, m0->m_pkthdr.len, error); 825 } 826 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 827 __func__, dmat, dmat->flags, error, nsegs); 828 return (error); 829} 830 831int 832bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 833 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 834 int flags) 835{ 836 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags)); 837} 838 839/* 840 * Like _bus_dmamap_load(), but for uios. 841 */ 842int 843bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 844 struct uio *uio, 845 bus_dmamap_callback2_t *callback, void *callback_arg, 846 int flags) 847{ 848 bus_addr_t lastaddr; 849 int nsegs, error, first, i; 850 bus_size_t resid; 851 struct iovec *iov; 852 pmap_t pmap; 853 854 flags |= BUS_DMA_NOWAIT; 855 resid = uio->uio_resid; 856 iov = uio->uio_iov; 857 858 if (uio->uio_segflg == UIO_USERSPACE) { 859 KASSERT(uio->uio_td != NULL, 860 ("bus_dmamap_load_uio: USERSPACE but no proc")); 861 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 862 } else 863 pmap = NULL; 864 865 nsegs = 0; 866 error = 0; 867 first = 1; 868 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 869 /* 870 * Now at the first iovec to load. Load each iovec 871 * until we have exhausted the residual count. 872 */ 873 bus_size_t minlen = 874 resid < iov[i].iov_len ? resid : iov[i].iov_len; 875 caddr_t addr = (caddr_t) iov[i].iov_base; 876 877 if (minlen > 0) { 878 error = _bus_dmamap_load_buffer(dmat, map, 879 addr, minlen, pmap, flags, &lastaddr, 880 dmat->segments, &nsegs, first); 881 first = 0; 882 883 resid -= minlen; 884 } 885 } 886 887 if (error) { 888 /* force "no valid mappings" in callback */ 889 (*callback)(callback_arg, dmat->segments, 0, 0, error); 890 } else { 891 (*callback)(callback_arg, dmat->segments, 892 nsegs+1, uio->uio_resid, error); 893 } 894 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 895 __func__, dmat, dmat->flags, error, nsegs + 1); 896 return (error); 897} 898 899/* 900 * Release the mapping held by map. 901 */ 902void 903_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 904{ 905 struct bounce_page *bpage; 906 907 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 908 STAILQ_REMOVE_HEAD(&map->bpages, links); 909 free_bounce_page(dmat, bpage); 910 } 911} 912 913void 914_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 915{ 916 struct bounce_page *bpage; 917 918 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 919 /* 920 * Handle data bouncing. We might also 921 * want to add support for invalidating 922 * the caches on broken hardware 923 */ 924 dmat->bounce_zone->total_bounced++; 925 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 926 "performing bounce", __func__, op, dmat, dmat->flags); 927 928 if (op & BUS_DMASYNC_PREWRITE) { 929 while (bpage != NULL) { 930 bcopy((void *)bpage->datavaddr, 931 (void *)bpage->vaddr, 932 bpage->datacount); 933 bpage = STAILQ_NEXT(bpage, links); 934 } 935 } 936 937 if (op & BUS_DMASYNC_POSTREAD) { 938 while (bpage != NULL) { 939 bcopy((void *)bpage->vaddr, 940 (void *)bpage->datavaddr, 941 bpage->datacount); 942 bpage = STAILQ_NEXT(bpage, links); 943 } 944 } 945 } 946} 947 948static void 949init_bounce_pages(void *dummy __unused) 950{ 951 952 total_bpages = 0; 953 STAILQ_INIT(&bounce_zone_list); 954 STAILQ_INIT(&bounce_map_waitinglist); 955 STAILQ_INIT(&bounce_map_callbacklist); 956 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 957} 958SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 959 960static struct sysctl_ctx_list * 961busdma_sysctl_tree(struct bounce_zone *bz) 962{ 963 return (&bz->sysctl_tree); 964} 965 966static struct sysctl_oid * 967busdma_sysctl_tree_top(struct bounce_zone *bz) 968{ 969 return (bz->sysctl_tree_top); 970} 971 972static int 973alloc_bounce_zone(bus_dma_tag_t dmat) 974{ 975 struct bounce_zone *bz; 976 977 /* Check to see if we already have a suitable zone */ 978 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 979 if ((dmat->alignment <= bz->alignment) 980 && (dmat->boundary <= bz->boundary) 981 && (dmat->lowaddr >= bz->lowaddr)) { 982 dmat->bounce_zone = bz; 983 return (0); 984 } 985 } 986 987 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 988 M_NOWAIT | M_ZERO)) == NULL) 989 return (ENOMEM); 990 991 STAILQ_INIT(&bz->bounce_page_list); 992 bz->free_bpages = 0; 993 bz->reserved_bpages = 0; 994 bz->active_bpages = 0; 995 bz->lowaddr = dmat->lowaddr; 996 bz->alignment = dmat->alignment; 997 bz->boundary = dmat->boundary; 998 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 999 busdma_zonecount++; 1000 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1001 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1002 dmat->bounce_zone = bz; 1003 1004 sysctl_ctx_init(&bz->sysctl_tree); 1005 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1006 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1007 CTLFLAG_RD, 0, ""); 1008 if (bz->sysctl_tree_top == NULL) { 1009 sysctl_ctx_free(&bz->sysctl_tree); 1010 return (0); /* XXX error code? */ 1011 } 1012 1013 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1014 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1015 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1016 "Total bounce pages"); 1017 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1018 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1019 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1020 "Free bounce pages"); 1021 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1022 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1023 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1024 "Reserved bounce pages"); 1025 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1026 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1027 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1028 "Active bounce pages"); 1029 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1030 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1031 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1032 "Total bounce requests"); 1033 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1034 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1035 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1036 "Total bounce requests that were deferred"); 1037 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1038 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1039 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1040 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1041 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1042 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1043 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1045 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 1046 1047 return (0); 1048} 1049 1050static int 1051alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1052{ 1053 struct bounce_zone *bz; 1054 int count; 1055 1056 bz = dmat->bounce_zone; 1057 count = 0; 1058 while (numpages > 0) { 1059 struct bounce_page *bpage; 1060 1061 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1062 M_NOWAIT | M_ZERO); 1063 1064 if (bpage == NULL) 1065 break; 1066 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1067 M_NOWAIT, 0ul, 1068 bz->lowaddr, 1069 PAGE_SIZE, 1070 bz->boundary); 1071 if (bpage->vaddr == 0) { 1072 free(bpage, M_DEVBUF); 1073 break; 1074 } 1075 bpage->busaddr = pmap_kextract(bpage->vaddr); 1076 mtx_lock(&bounce_lock); 1077 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1078 total_bpages++; 1079 bz->total_bpages++; 1080 bz->free_bpages++; 1081 mtx_unlock(&bounce_lock); 1082 count++; 1083 numpages--; 1084 } 1085 return (count); 1086} 1087 1088static int 1089reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1090{ 1091 struct bounce_zone *bz; 1092 int pages; 1093 1094 mtx_assert(&bounce_lock, MA_OWNED); 1095 bz = dmat->bounce_zone; 1096 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1097 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1098 return (map->pagesneeded - (map->pagesreserved + pages)); 1099 bz->free_bpages -= pages; 1100 bz->reserved_bpages += pages; 1101 map->pagesreserved += pages; 1102 pages = map->pagesneeded - map->pagesreserved; 1103 1104 return (pages); 1105} 1106 1107static bus_addr_t 1108add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1109 bus_size_t size) 1110{ 1111 struct bounce_zone *bz; 1112 struct bounce_page *bpage; 1113 1114 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1115 KASSERT(map != NULL && map != &nobounce_dmamap, 1116 ("add_bounce_page: bad map %p", map)); 1117 1118 bz = dmat->bounce_zone; 1119 if (map->pagesneeded == 0) 1120 panic("add_bounce_page: map doesn't need any pages"); 1121 map->pagesneeded--; 1122 1123 if (map->pagesreserved == 0) 1124 panic("add_bounce_page: map doesn't need any pages"); 1125 map->pagesreserved--; 1126 1127 mtx_lock(&bounce_lock); 1128 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1129 if (bpage == NULL) 1130 panic("add_bounce_page: free page list is empty"); 1131 1132 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1133 bz->reserved_bpages--; 1134 bz->active_bpages++; 1135 mtx_unlock(&bounce_lock); 1136 1137 bpage->datavaddr = vaddr; 1138 bpage->datacount = size; 1139 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1140 return (bpage->busaddr); 1141} 1142 1143static void 1144free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1145{ 1146 struct bus_dmamap *map; 1147 struct bounce_zone *bz; 1148 1149 bz = dmat->bounce_zone; 1150 bpage->datavaddr = 0; 1151 bpage->datacount = 0; 1152 1153 mtx_lock(&bounce_lock); 1154 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1155 bz->free_bpages++; 1156 bz->active_bpages--; 1157 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1158 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1159 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1160 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1161 map, links); 1162 busdma_swi_pending = 1; 1163 bz->total_deferred++; 1164 swi_sched(vm_ih, 0); 1165 } 1166 } 1167 mtx_unlock(&bounce_lock); 1168} 1169 1170void 1171busdma_swi(void) 1172{ 1173 bus_dma_tag_t dmat; 1174 struct bus_dmamap *map; 1175 1176 mtx_lock(&bounce_lock); 1177 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1178 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1179 mtx_unlock(&bounce_lock); 1180 dmat = map->dmat; 1181 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1182 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1183 map->callback, map->callback_arg, /*flags*/0); 1184 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1185 mtx_lock(&bounce_lock); 1186 } 1187 mtx_unlock(&bounce_lock); 1188} 1189