busdma_machdep.c revision 251900
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/x86/x86/busdma_machdep.c 251900 2013-06-18 06:55:58Z rpaulo $"); 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/memdesc.h> 40#include <sys/mutex.h> 41#include <sys/sysctl.h> 42#include <sys/uio.h> 43 44#include <vm/vm.h> 45#include <vm/vm_extern.h> 46#include <vm/vm_kern.h> 47#include <vm/vm_page.h> 48#include <vm/vm_map.h> 49 50#include <machine/atomic.h> 51#include <machine/bus.h> 52#include <machine/md_var.h> 53#include <machine/specialreg.h> 54 55#ifdef __i386__ 56#define MAX_BPAGES 512 57#else 58#define MAX_BPAGES 8192 59#endif 60#define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 61#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 62 63struct bounce_zone; 64 65struct bus_dma_tag { 66 bus_dma_tag_t parent; 67 bus_size_t alignment; 68 bus_addr_t boundary; 69 bus_addr_t lowaddr; 70 bus_addr_t highaddr; 71 bus_dma_filter_t *filter; 72 void *filterarg; 73 bus_size_t maxsize; 74 u_int nsegments; 75 bus_size_t maxsegsz; 76 int flags; 77 int ref_count; 78 int map_count; 79 bus_dma_lock_t *lockfunc; 80 void *lockfuncarg; 81 bus_dma_segment_t *segments; 82 struct bounce_zone *bounce_zone; 83}; 84 85struct bounce_page { 86 vm_offset_t vaddr; /* kva of bounce buffer */ 87 bus_addr_t busaddr; /* Physical address */ 88 vm_offset_t datavaddr; /* kva of client data */ 89 bus_addr_t dataaddr; /* client physical address */ 90 bus_size_t datacount; /* client data count */ 91 STAILQ_ENTRY(bounce_page) links; 92}; 93 94int busdma_swi_pending; 95 96struct bounce_zone { 97 STAILQ_ENTRY(bounce_zone) links; 98 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 99 int total_bpages; 100 int free_bpages; 101 int reserved_bpages; 102 int active_bpages; 103 int total_bounced; 104 int total_deferred; 105 int map_count; 106 bus_size_t alignment; 107 bus_addr_t lowaddr; 108 char zoneid[8]; 109 char lowaddrid[20]; 110 struct sysctl_ctx_list sysctl_tree; 111 struct sysctl_oid *sysctl_tree_top; 112}; 113 114static struct mtx bounce_lock; 115static int total_bpages; 116static int busdma_zonecount; 117static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 118 119static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 120SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 121 "Total bounce pages"); 122 123struct bus_dmamap { 124 struct bp_list bpages; 125 int pagesneeded; 126 int pagesreserved; 127 bus_dma_tag_t dmat; 128 struct memdesc mem; 129 bus_dmamap_callback_t *callback; 130 void *callback_arg; 131 STAILQ_ENTRY(bus_dmamap) links; 132}; 133 134static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 135static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 136static struct bus_dmamap nobounce_dmamap, contig_dmamap; 137 138static void init_bounce_pages(void *dummy); 139static int alloc_bounce_zone(bus_dma_tag_t dmat); 140static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 141static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 142 int commit); 143static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 144 vm_offset_t vaddr, bus_addr_t addr, 145 bus_size_t size); 146static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 147int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 148static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 149 pmap_t pmap, void *buf, bus_size_t buflen, 150 int flags); 151static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 152 vm_paddr_t buf, bus_size_t buflen, 153 int flags); 154static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 155 int flags); 156 157#ifdef XEN 158#undef pmap_kextract 159#define pmap_kextract pmap_kextract_ma 160#endif 161 162/* 163 * Return true if a match is made. 164 * 165 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 166 * 167 * If paddr is within the bounds of the dma tag then call the filter callback 168 * to check for a match, if there is no filter callback then assume a match. 169 */ 170int 171run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 172{ 173 int retval; 174 175 retval = 0; 176 177 do { 178 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 179 || ((paddr & (dmat->alignment - 1)) != 0)) 180 && (dmat->filter == NULL 181 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 182 retval = 1; 183 184 dmat = dmat->parent; 185 } while (retval == 0 && dmat != NULL); 186 return (retval); 187} 188 189/* 190 * Convenience function for manipulating driver locks from busdma (during 191 * busdma_swi, for example). Drivers that don't provide their own locks 192 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 193 * non-mutex locking scheme don't have to use this at all. 194 */ 195void 196busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 197{ 198 struct mtx *dmtx; 199 200 dmtx = (struct mtx *)arg; 201 switch (op) { 202 case BUS_DMA_LOCK: 203 mtx_lock(dmtx); 204 break; 205 case BUS_DMA_UNLOCK: 206 mtx_unlock(dmtx); 207 break; 208 default: 209 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 210 } 211} 212 213/* 214 * dflt_lock should never get called. It gets put into the dma tag when 215 * lockfunc == NULL, which is only valid if the maps that are associated 216 * with the tag are meant to never be defered. 217 * XXX Should have a way to identify which driver is responsible here. 218 */ 219static void 220dflt_lock(void *arg, bus_dma_lock_op_t op) 221{ 222 panic("driver error: busdma dflt_lock called"); 223} 224 225/* 226 * Allocate a device specific dma_tag. 227 */ 228int 229bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 230 bus_addr_t boundary, bus_addr_t lowaddr, 231 bus_addr_t highaddr, bus_dma_filter_t *filter, 232 void *filterarg, bus_size_t maxsize, int nsegments, 233 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 234 void *lockfuncarg, bus_dma_tag_t *dmat) 235{ 236 bus_dma_tag_t newtag; 237 int error = 0; 238 239 /* Basic sanity checking */ 240 if (boundary != 0 && boundary < maxsegsz) 241 maxsegsz = boundary; 242 243 if (maxsegsz == 0) { 244 return (EINVAL); 245 } 246 247 /* Return a NULL tag on failure */ 248 *dmat = NULL; 249 250 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 251 M_ZERO | M_NOWAIT); 252 if (newtag == NULL) { 253 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 254 __func__, newtag, 0, ENOMEM); 255 return (ENOMEM); 256 } 257 258 newtag->parent = parent; 259 newtag->alignment = alignment; 260 newtag->boundary = boundary; 261 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 262 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 263 newtag->filter = filter; 264 newtag->filterarg = filterarg; 265 newtag->maxsize = maxsize; 266 newtag->nsegments = nsegments; 267 newtag->maxsegsz = maxsegsz; 268 newtag->flags = flags; 269 newtag->ref_count = 1; /* Count ourself */ 270 newtag->map_count = 0; 271 if (lockfunc != NULL) { 272 newtag->lockfunc = lockfunc; 273 newtag->lockfuncarg = lockfuncarg; 274 } else { 275 newtag->lockfunc = dflt_lock; 276 newtag->lockfuncarg = NULL; 277 } 278 newtag->segments = NULL; 279 280 /* Take into account any restrictions imposed by our parent tag */ 281 if (parent != NULL) { 282 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 283 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 284 if (newtag->boundary == 0) 285 newtag->boundary = parent->boundary; 286 else if (parent->boundary != 0) 287 newtag->boundary = MIN(parent->boundary, 288 newtag->boundary); 289 if ((newtag->filter != NULL) || 290 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0)) 291 newtag->flags |= BUS_DMA_COULD_BOUNCE; 292 if (newtag->filter == NULL) { 293 /* 294 * Short circuit looking at our parent directly 295 * since we have encapsulated all of its information 296 */ 297 newtag->filter = parent->filter; 298 newtag->filterarg = parent->filterarg; 299 newtag->parent = parent->parent; 300 } 301 if (newtag->parent != NULL) 302 atomic_add_int(&parent->ref_count, 1); 303 } 304 305 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 306 || newtag->alignment > 1) 307 newtag->flags |= BUS_DMA_COULD_BOUNCE; 308 309 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 310 (flags & BUS_DMA_ALLOCNOW) != 0) { 311 struct bounce_zone *bz; 312 313 /* Must bounce */ 314 315 if ((error = alloc_bounce_zone(newtag)) != 0) { 316 free(newtag, M_DEVBUF); 317 return (error); 318 } 319 bz = newtag->bounce_zone; 320 321 if (ptoa(bz->total_bpages) < maxsize) { 322 int pages; 323 324 pages = atop(maxsize) - bz->total_bpages; 325 326 /* Add pages to our bounce pool */ 327 if (alloc_bounce_pages(newtag, pages) < pages) 328 error = ENOMEM; 329 } 330 /* Performed initial allocation */ 331 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 332 } 333 334 if (error != 0) { 335 free(newtag, M_DEVBUF); 336 } else { 337 *dmat = newtag; 338 } 339 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 340 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 341 return (error); 342} 343 344int 345bus_dma_tag_destroy(bus_dma_tag_t dmat) 346{ 347 bus_dma_tag_t dmat_copy; 348 int error; 349 350 error = 0; 351 dmat_copy = dmat; 352 353 if (dmat != NULL) { 354 355 if (dmat->map_count != 0) { 356 error = EBUSY; 357 goto out; 358 } 359 360 while (dmat != NULL) { 361 bus_dma_tag_t parent; 362 363 parent = dmat->parent; 364 atomic_subtract_int(&dmat->ref_count, 1); 365 if (dmat->ref_count == 0) { 366 if (dmat->segments != NULL) 367 free(dmat->segments, M_DEVBUF); 368 free(dmat, M_DEVBUF); 369 /* 370 * Last reference count, so 371 * release our reference 372 * count on our parent. 373 */ 374 dmat = parent; 375 } else 376 dmat = NULL; 377 } 378 } 379out: 380 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 381 return (error); 382} 383 384/* 385 * Allocate a handle for mapping from kva/uva/physical 386 * address space into bus device space. 387 */ 388int 389bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 390{ 391 int error; 392 393 error = 0; 394 395 if (dmat->segments == NULL) { 396 dmat->segments = (bus_dma_segment_t *)malloc( 397 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 398 M_NOWAIT); 399 if (dmat->segments == NULL) { 400 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 401 __func__, dmat, ENOMEM); 402 return (ENOMEM); 403 } 404 } 405 406 /* 407 * Bouncing might be required if the driver asks for an active 408 * exclusion region, a data alignment that is stricter than 1, and/or 409 * an active address boundary. 410 */ 411 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 412 413 /* Must bounce */ 414 struct bounce_zone *bz; 415 int maxpages; 416 417 if (dmat->bounce_zone == NULL) { 418 if ((error = alloc_bounce_zone(dmat)) != 0) 419 return (error); 420 } 421 bz = dmat->bounce_zone; 422 423 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 424 M_NOWAIT | M_ZERO); 425 if (*mapp == NULL) { 426 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 427 __func__, dmat, ENOMEM); 428 return (ENOMEM); 429 } 430 431 /* Initialize the new map */ 432 STAILQ_INIT(&((*mapp)->bpages)); 433 434 /* 435 * Attempt to add pages to our pool on a per-instance 436 * basis up to a sane limit. 437 */ 438 if (dmat->alignment > 1) 439 maxpages = MAX_BPAGES; 440 else 441 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 442 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 443 || (bz->map_count > 0 && bz->total_bpages < maxpages)) { 444 int pages; 445 446 pages = MAX(atop(dmat->maxsize), 1); 447 pages = MIN(maxpages - bz->total_bpages, pages); 448 pages = MAX(pages, 1); 449 if (alloc_bounce_pages(dmat, pages) < pages) 450 error = ENOMEM; 451 452 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 453 if (error == 0) 454 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 455 } else { 456 error = 0; 457 } 458 } 459 bz->map_count++; 460 } else { 461 *mapp = NULL; 462 } 463 if (error == 0) 464 dmat->map_count++; 465 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 466 __func__, dmat, dmat->flags, error); 467 return (error); 468} 469 470/* 471 * Destroy a handle for mapping from kva/uva/physical 472 * address space into bus device space. 473 */ 474int 475bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 476{ 477 if (map != NULL && map != &nobounce_dmamap && map != &contig_dmamap) { 478 if (STAILQ_FIRST(&map->bpages) != NULL) { 479 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 480 __func__, dmat, EBUSY); 481 return (EBUSY); 482 } 483 if (dmat->bounce_zone) 484 dmat->bounce_zone->map_count--; 485 free(map, M_DEVBUF); 486 } 487 dmat->map_count--; 488 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 489 return (0); 490} 491 492 493/* 494 * Allocate a piece of memory that can be efficiently mapped into 495 * bus device space based on the constraints lited in the dma tag. 496 * A dmamap to for use with dmamap_load is also allocated. 497 */ 498int 499bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 500 bus_dmamap_t *mapp) 501{ 502 vm_memattr_t attr; 503 int mflags; 504 505 if (flags & BUS_DMA_NOWAIT) 506 mflags = M_NOWAIT; 507 else 508 mflags = M_WAITOK; 509 510 /* If we succeed, no mapping/bouncing will be required */ 511 *mapp = NULL; 512 513 if (dmat->segments == NULL) { 514 dmat->segments = (bus_dma_segment_t *)malloc( 515 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 516 mflags); 517 if (dmat->segments == NULL) { 518 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 519 __func__, dmat, dmat->flags, ENOMEM); 520 return (ENOMEM); 521 } 522 } 523 if (flags & BUS_DMA_ZERO) 524 mflags |= M_ZERO; 525 if (flags & BUS_DMA_NOCACHE) 526 attr = VM_MEMATTR_UNCACHEABLE; 527 else 528 attr = VM_MEMATTR_DEFAULT; 529 530 /* 531 * XXX: 532 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 533 * alignment guarantees of malloc need to be nailed down, and the 534 * code below should be rewritten to take that into account. 535 * 536 * In the meantime, we'll warn the user if malloc gets it wrong. 537 */ 538 if ((dmat->maxsize <= PAGE_SIZE) && 539 (dmat->alignment < dmat->maxsize) && 540 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) && 541 attr == VM_MEMATTR_DEFAULT) { 542 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 543 } else if (dmat->nsegments >= btoc(dmat->maxsize) && 544 dmat->alignment <= PAGE_SIZE && 545 (dmat->boundary == 0 || dmat->boundary >= dmat->lowaddr)) { 546 /* Page-based multi-segment allocations allowed */ 547 *vaddr = (void *)kmem_alloc_attr(kernel_map, dmat->maxsize, 548 mflags, 0ul, dmat->lowaddr, attr); 549 *mapp = &contig_dmamap; 550 } else { 551 *vaddr = (void *)kmem_alloc_contig(kernel_map, dmat->maxsize, 552 mflags, 0ul, dmat->lowaddr, dmat->alignment ? 553 dmat->alignment : 1ul, dmat->boundary, attr); 554 *mapp = &contig_dmamap; 555 } 556 if (*vaddr == NULL) { 557 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 558 __func__, dmat, dmat->flags, ENOMEM); 559 return (ENOMEM); 560 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) { 561 printf("bus_dmamem_alloc failed to align memory properly.\n"); 562 } 563 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 564 __func__, dmat, dmat->flags, 0); 565 return (0); 566} 567 568/* 569 * Free a piece of memory and it's allociated dmamap, that was allocated 570 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 571 */ 572void 573bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 574{ 575 /* 576 * dmamem does not need to be bounced, so the map should be 577 * NULL if malloc() was used and contig_dmamap if 578 * kmem_alloc_contig() was used. 579 */ 580 if (!(map == NULL || map == &contig_dmamap)) 581 panic("bus_dmamem_free: Invalid map freed\n"); 582 if (map == NULL) 583 free(vaddr, M_DEVBUF); 584 else 585 kmem_free(kernel_map, (vm_offset_t)vaddr, dmat->maxsize); 586 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 587} 588 589static void 590_bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 591 bus_size_t buflen, int flags) 592{ 593 bus_addr_t curaddr; 594 bus_size_t sgsize; 595 596 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 597 /* 598 * Count the number of bounce pages 599 * needed in order to complete this transfer 600 */ 601 curaddr = buf; 602 while (buflen != 0) { 603 sgsize = MIN(buflen, dmat->maxsegsz); 604 if (run_filter(dmat, curaddr)) { 605 sgsize = MIN(sgsize, PAGE_SIZE); 606 map->pagesneeded++; 607 } 608 curaddr += sgsize; 609 buflen -= sgsize; 610 } 611 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 612 } 613} 614 615static void 616_bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 617 void *buf, bus_size_t buflen, int flags) 618{ 619 vm_offset_t vaddr; 620 vm_offset_t vendaddr; 621 bus_addr_t paddr; 622 623 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 624 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 625 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 626 dmat->boundary, dmat->alignment); 627 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 628 map, &nobounce_dmamap, map->pagesneeded); 629 /* 630 * Count the number of bounce pages 631 * needed in order to complete this transfer 632 */ 633 vaddr = (vm_offset_t)buf; 634 vendaddr = (vm_offset_t)buf + buflen; 635 636 while (vaddr < vendaddr) { 637 bus_size_t sg_len; 638 639 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 640 if (pmap == kernel_pmap) 641 paddr = pmap_kextract(vaddr); 642 else 643 paddr = pmap_extract(pmap, vaddr); 644 if (run_filter(dmat, paddr) != 0) { 645 sg_len = roundup2(sg_len, dmat->alignment); 646 map->pagesneeded++; 647 } 648 vaddr += sg_len; 649 } 650 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 651 } 652} 653 654static int 655_bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 656{ 657 658 /* Reserve Necessary Bounce Pages */ 659 mtx_lock(&bounce_lock); 660 if (flags & BUS_DMA_NOWAIT) { 661 if (reserve_bounce_pages(dmat, map, 0) != 0) { 662 mtx_unlock(&bounce_lock); 663 return (ENOMEM); 664 } 665 } else { 666 if (reserve_bounce_pages(dmat, map, 1) != 0) { 667 /* Queue us for resources */ 668 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 669 mtx_unlock(&bounce_lock); 670 return (EINPROGRESS); 671 } 672 } 673 mtx_unlock(&bounce_lock); 674 675 return (0); 676} 677 678/* 679 * Add a single contiguous physical range to the segment list. 680 */ 681static int 682_bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr, 683 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 684{ 685 bus_addr_t baddr, bmask; 686 int seg; 687 688 /* 689 * Make sure we don't cross any boundaries. 690 */ 691 bmask = ~(dmat->boundary - 1); 692 if (dmat->boundary > 0) { 693 baddr = (curaddr + dmat->boundary) & bmask; 694 if (sgsize > (baddr - curaddr)) 695 sgsize = (baddr - curaddr); 696 } 697 698 /* 699 * Insert chunk into a segment, coalescing with 700 * previous segment if possible. 701 */ 702 seg = *segp; 703 if (seg == -1) { 704 seg = 0; 705 segs[seg].ds_addr = curaddr; 706 segs[seg].ds_len = sgsize; 707 } else { 708 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 709 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 710 (dmat->boundary == 0 || 711 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 712 segs[seg].ds_len += sgsize; 713 else { 714 if (++seg >= dmat->nsegments) 715 return (0); 716 segs[seg].ds_addr = curaddr; 717 segs[seg].ds_len = sgsize; 718 } 719 } 720 *segp = seg; 721 return (sgsize); 722} 723 724/* 725 * Utility function to load a physical buffer. segp contains 726 * the starting segment on entrace, and the ending segment on exit. 727 */ 728int 729_bus_dmamap_load_phys(bus_dma_tag_t dmat, 730 bus_dmamap_t map, 731 vm_paddr_t buf, bus_size_t buflen, 732 int flags, 733 bus_dma_segment_t *segs, 734 int *segp) 735{ 736 bus_size_t sgsize; 737 bus_addr_t curaddr; 738 int error; 739 740 if (map == NULL || map == &contig_dmamap) 741 map = &nobounce_dmamap; 742 743 if (segs == NULL) 744 segs = dmat->segments; 745 746 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) { 747 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 748 if (map->pagesneeded != 0) { 749 error = _bus_dmamap_reserve_pages(dmat, map, flags); 750 if (error) 751 return (error); 752 } 753 } 754 755 while (buflen > 0) { 756 curaddr = buf; 757 sgsize = MIN(buflen, dmat->maxsegsz); 758 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 759 map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 760 sgsize = MIN(sgsize, PAGE_SIZE); 761 curaddr = add_bounce_page(dmat, map, 0, curaddr, 762 sgsize); 763 } 764 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 765 segp); 766 if (sgsize == 0) 767 break; 768 buf += sgsize; 769 buflen -= sgsize; 770 } 771 772 /* 773 * Did we fit? 774 */ 775 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 776} 777 778/* 779 * Utility function to load a linear buffer. segp contains 780 * the starting segment on entrace, and the ending segment on exit. 781 */ 782int 783_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 784 bus_dmamap_t map, 785 void *buf, bus_size_t buflen, 786 pmap_t pmap, 787 int flags, 788 bus_dma_segment_t *segs, 789 int *segp) 790{ 791 bus_size_t sgsize; 792 bus_addr_t curaddr; 793 vm_offset_t vaddr; 794 int error; 795 796 if (map == NULL || map == &contig_dmamap) 797 map = &nobounce_dmamap; 798 799 if (segs == NULL) 800 segs = dmat->segments; 801 802 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) { 803 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 804 if (map->pagesneeded != 0) { 805 error = _bus_dmamap_reserve_pages(dmat, map, flags); 806 if (error) 807 return (error); 808 } 809 } 810 811 vaddr = (vm_offset_t)buf; 812 813 while (buflen > 0) { 814 bus_size_t max_sgsize; 815 816 /* 817 * Get the physical address for this segment. 818 */ 819 if (pmap == kernel_pmap) 820 curaddr = pmap_kextract(vaddr); 821 else 822 curaddr = pmap_extract(pmap, vaddr); 823 824 /* 825 * Compute the segment size, and adjust counts. 826 */ 827 max_sgsize = MIN(buflen, dmat->maxsegsz); 828 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); 829 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 830 map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 831 sgsize = roundup2(sgsize, dmat->alignment); 832 sgsize = MIN(sgsize, max_sgsize); 833 curaddr = add_bounce_page(dmat, map, vaddr, curaddr, 834 sgsize); 835 } else { 836 sgsize = MIN(sgsize, max_sgsize); 837 } 838 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 839 segp); 840 if (sgsize == 0) 841 break; 842 vaddr += sgsize; 843 buflen -= sgsize; 844 } 845 846 /* 847 * Did we fit? 848 */ 849 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 850} 851 852void 853__bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 854 struct memdesc *mem, bus_dmamap_callback_t *callback, 855 void *callback_arg) 856{ 857 if (map != NULL) { 858 map->mem = *mem; 859 map->dmat = dmat; 860 map->callback = callback; 861 map->callback_arg = callback_arg; 862 } 863} 864 865bus_dma_segment_t * 866_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 867 bus_dma_segment_t *segs, int nsegs, int error) 868{ 869 870 if (segs == NULL) 871 segs = dmat->segments; 872 return (segs); 873} 874 875/* 876 * Release the mapping held by map. 877 */ 878void 879_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 880{ 881 struct bounce_page *bpage; 882 883 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 884 STAILQ_REMOVE_HEAD(&map->bpages, links); 885 free_bounce_page(dmat, bpage); 886 } 887} 888 889void 890_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 891{ 892 struct bounce_page *bpage; 893 894 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 895 /* 896 * Handle data bouncing. We might also 897 * want to add support for invalidating 898 * the caches on broken hardware 899 */ 900 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 901 "performing bounce", __func__, dmat, dmat->flags, op); 902 903 if (op & BUS_DMASYNC_PREWRITE) { 904 while (bpage != NULL) { 905 if (bpage->datavaddr != 0) 906 bcopy((void *)bpage->datavaddr, 907 (void *)bpage->vaddr, 908 bpage->datacount); 909 else 910 physcopyout(bpage->dataaddr, 911 (void *)bpage->vaddr, 912 bpage->datacount); 913 bpage = STAILQ_NEXT(bpage, links); 914 } 915 dmat->bounce_zone->total_bounced++; 916 } 917 918 if (op & BUS_DMASYNC_POSTREAD) { 919 while (bpage != NULL) { 920 if (bpage->datavaddr != 0) 921 bcopy((void *)bpage->vaddr, 922 (void *)bpage->datavaddr, 923 bpage->datacount); 924 else 925 physcopyin((void *)bpage->vaddr, 926 bpage->dataaddr, 927 bpage->datacount); 928 bpage = STAILQ_NEXT(bpage, links); 929 } 930 dmat->bounce_zone->total_bounced++; 931 } 932 } 933} 934 935static void 936init_bounce_pages(void *dummy __unused) 937{ 938 939 total_bpages = 0; 940 STAILQ_INIT(&bounce_zone_list); 941 STAILQ_INIT(&bounce_map_waitinglist); 942 STAILQ_INIT(&bounce_map_callbacklist); 943 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 944} 945SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 946 947static struct sysctl_ctx_list * 948busdma_sysctl_tree(struct bounce_zone *bz) 949{ 950 return (&bz->sysctl_tree); 951} 952 953static struct sysctl_oid * 954busdma_sysctl_tree_top(struct bounce_zone *bz) 955{ 956 return (bz->sysctl_tree_top); 957} 958 959#if defined(__amd64__) || defined(PAE) 960#define SYSCTL_ADD_BUS_SIZE_T SYSCTL_ADD_UQUAD 961#else 962#define SYSCTL_ADD_BUS_SIZE_T(ctx, parent, nbr, name, flag, ptr, desc) \ 963 SYSCTL_ADD_UINT(ctx, parent, nbr, name, flag, ptr, 0, desc) 964#endif 965 966static int 967alloc_bounce_zone(bus_dma_tag_t dmat) 968{ 969 struct bounce_zone *bz; 970 971 /* Check to see if we already have a suitable zone */ 972 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 973 if ((dmat->alignment <= bz->alignment) 974 && (dmat->lowaddr >= bz->lowaddr)) { 975 dmat->bounce_zone = bz; 976 return (0); 977 } 978 } 979 980 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 981 M_NOWAIT | M_ZERO)) == NULL) 982 return (ENOMEM); 983 984 STAILQ_INIT(&bz->bounce_page_list); 985 bz->free_bpages = 0; 986 bz->reserved_bpages = 0; 987 bz->active_bpages = 0; 988 bz->lowaddr = dmat->lowaddr; 989 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 990 bz->map_count = 0; 991 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 992 busdma_zonecount++; 993 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 994 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 995 dmat->bounce_zone = bz; 996 997 sysctl_ctx_init(&bz->sysctl_tree); 998 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 999 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1000 CTLFLAG_RD, 0, ""); 1001 if (bz->sysctl_tree_top == NULL) { 1002 sysctl_ctx_free(&bz->sysctl_tree); 1003 return (0); /* XXX error code? */ 1004 } 1005 1006 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1007 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1008 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1009 "Total bounce pages"); 1010 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1011 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1012 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1013 "Free bounce pages"); 1014 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1016 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1017 "Reserved bounce pages"); 1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1020 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1021 "Active bounce pages"); 1022 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1023 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1024 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1025 "Total bounce requests"); 1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1028 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1029 "Total bounce requests that were deferred"); 1030 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1032 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1033 SYSCTL_ADD_BUS_SIZE_T(busdma_sysctl_tree(bz), 1034 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1035 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1036 1037 return (0); 1038} 1039 1040static int 1041alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1042{ 1043 struct bounce_zone *bz; 1044 int count; 1045 1046 bz = dmat->bounce_zone; 1047 count = 0; 1048 while (numpages > 0) { 1049 struct bounce_page *bpage; 1050 1051 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1052 M_NOWAIT | M_ZERO); 1053 1054 if (bpage == NULL) 1055 break; 1056 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1057 M_NOWAIT, 0ul, 1058 bz->lowaddr, 1059 PAGE_SIZE, 1060 0); 1061 if (bpage->vaddr == 0) { 1062 free(bpage, M_DEVBUF); 1063 break; 1064 } 1065 bpage->busaddr = pmap_kextract(bpage->vaddr); 1066 mtx_lock(&bounce_lock); 1067 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1068 total_bpages++; 1069 bz->total_bpages++; 1070 bz->free_bpages++; 1071 mtx_unlock(&bounce_lock); 1072 count++; 1073 numpages--; 1074 } 1075 return (count); 1076} 1077 1078static int 1079reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1080{ 1081 struct bounce_zone *bz; 1082 int pages; 1083 1084 mtx_assert(&bounce_lock, MA_OWNED); 1085 bz = dmat->bounce_zone; 1086 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1087 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1088 return (map->pagesneeded - (map->pagesreserved + pages)); 1089 bz->free_bpages -= pages; 1090 bz->reserved_bpages += pages; 1091 map->pagesreserved += pages; 1092 pages = map->pagesneeded - map->pagesreserved; 1093 1094 return (pages); 1095} 1096 1097static bus_addr_t 1098add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1099 bus_addr_t addr, bus_size_t size) 1100{ 1101 struct bounce_zone *bz; 1102 struct bounce_page *bpage; 1103 1104 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1105 KASSERT(map != NULL && map != &nobounce_dmamap && map != &contig_dmamap, 1106 ("add_bounce_page: bad map %p", map)); 1107 1108 bz = dmat->bounce_zone; 1109 if (map->pagesneeded == 0) 1110 panic("add_bounce_page: map doesn't need any pages"); 1111 map->pagesneeded--; 1112 1113 if (map->pagesreserved == 0) 1114 panic("add_bounce_page: map doesn't need any pages"); 1115 map->pagesreserved--; 1116 1117 mtx_lock(&bounce_lock); 1118 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1119 if (bpage == NULL) 1120 panic("add_bounce_page: free page list is empty"); 1121 1122 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1123 bz->reserved_bpages--; 1124 bz->active_bpages++; 1125 mtx_unlock(&bounce_lock); 1126 1127 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1128 /* Page offset needs to be preserved. */ 1129 bpage->vaddr |= vaddr & PAGE_MASK; 1130 bpage->busaddr |= vaddr & PAGE_MASK; 1131 } 1132 bpage->datavaddr = vaddr; 1133 bpage->dataaddr = addr; 1134 bpage->datacount = size; 1135 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1136 return (bpage->busaddr); 1137} 1138 1139static void 1140free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1141{ 1142 struct bus_dmamap *map; 1143 struct bounce_zone *bz; 1144 1145 bz = dmat->bounce_zone; 1146 bpage->datavaddr = 0; 1147 bpage->datacount = 0; 1148 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1149 /* 1150 * Reset the bounce page to start at offset 0. Other uses 1151 * of this bounce page may need to store a full page of 1152 * data and/or assume it starts on a page boundary. 1153 */ 1154 bpage->vaddr &= ~PAGE_MASK; 1155 bpage->busaddr &= ~PAGE_MASK; 1156 } 1157 1158 mtx_lock(&bounce_lock); 1159 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1160 bz->free_bpages++; 1161 bz->active_bpages--; 1162 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1163 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1164 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1165 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1166 map, links); 1167 busdma_swi_pending = 1; 1168 bz->total_deferred++; 1169 swi_sched(vm_ih, 0); 1170 } 1171 } 1172 mtx_unlock(&bounce_lock); 1173} 1174 1175void 1176busdma_swi(void) 1177{ 1178 bus_dma_tag_t dmat; 1179 struct bus_dmamap *map; 1180 1181 mtx_lock(&bounce_lock); 1182 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1183 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1184 mtx_unlock(&bounce_lock); 1185 dmat = map->dmat; 1186 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1187 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1188 map->callback, map->callback_arg, 1189 BUS_DMA_WAITOK); 1190 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1191 mtx_lock(&bounce_lock); 1192 } 1193 mtx_unlock(&bounce_lock); 1194} 1195