1 /*- 2 * Copyright (c) 1997, 1998 Justin T. Gibbs. 3 * Copyright (c) 2015-2016 The FreeBSD Foundation 4 * All rights reserved. 5 * 6 * Portions of this software were developed by Andrew Turner 7 * under sponsorship of the FreeBSD Foundation. 8 * 9 * Portions of this software were developed by Semihalf 10 * under sponsorship of the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions, and the following disclaimer, 17 * without modification, immediately at the beginning of the file. 18 * 2. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 25 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/malloc.h> 40 #include <sys/bus.h> 41 #include <sys/interrupt.h> 42 #include <sys/kernel.h> 43 #include <sys/ktr.h> 44 #include <sys/lock.h> 45 #include <sys/proc.h> 46 #include <sys/memdesc.h> 47 #include <sys/mutex.h> 48 #include <sys/sysctl.h> 49 #include <sys/uio.h> 50 51 #include <vm/vm.h> 52 #include <vm/vm_extern.h> 53 #include <vm/vm_kern.h> 54 #include <vm/vm_page.h> 55 #include <vm/vm_map.h> 56 57 #include <machine/atomic.h> 58 #include <machine/bus.h> 59 #include <machine/md_var.h> 60 #include <machine/bus_dma_impl.h> 61 62 #define MAX_BPAGES 4096 63 64 enum { 65 BF_COULD_BOUNCE = 0x01, 66 BF_MIN_ALLOC_COMP = 0x02, 67 BF_KMEM_ALLOC = 0x04, 68 BF_COHERENT = 0x10, 69 }; 70 71 struct bounce_zone; 72 73 struct bus_dma_tag { 74 struct bus_dma_tag_common common; 75 int map_count; 76 int bounce_flags; 77 bus_dma_segment_t *segments; 78 struct bounce_zone *bounce_zone; 79 }; 80 81 struct bounce_page { 82 vm_offset_t vaddr; /* kva of bounce buffer */ 83 bus_addr_t busaddr; /* Physical address */ 84 vm_offset_t datavaddr; /* kva of client data */ 85 vm_page_t datapage; /* physical page of client data */ 86 vm_offset_t dataoffs; /* page offset of client data */ 87 bus_size_t datacount; /* client data count */ 88 STAILQ_ENTRY(bounce_page) links; 89 }; 90 91 int busdma_swi_pending; 92 93 struct bounce_zone { 94 STAILQ_ENTRY(bounce_zone) links; 95 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 96 int total_bpages; 97 int free_bpages; 98 int reserved_bpages; 99 int active_bpages; 100 int total_bounced; 101 int total_deferred; 102 int map_count; 103 bus_size_t alignment; 104 bus_addr_t lowaddr; 105 char zoneid[8]; 106 char lowaddrid[20]; 107 struct sysctl_ctx_list sysctl_tree; 108 struct sysctl_oid *sysctl_tree_top; 109 }; 110 111 static struct mtx bounce_lock; 112 static int total_bpages; 113 static int busdma_zonecount; 114 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 115 116 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 117 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 118 "Total bounce pages"); 119 120 struct sync_list { 121 vm_offset_t vaddr; /* kva of client data */ 122 bus_addr_t paddr; /* physical address */ 123 vm_page_t pages; /* starting page of client data */ 124 bus_size_t datacount; /* client data count */ 125 }; 126 127 struct bus_dmamap { 128 struct bp_list bpages; 129 int pagesneeded; 130 int pagesreserved; 131 bus_dma_tag_t dmat; 132 struct memdesc mem; 133 bus_dmamap_callback_t *callback; 134 void *callback_arg; 135 STAILQ_ENTRY(bus_dmamap) links; 136 u_int flags; 137 #define DMAMAP_COULD_BOUNCE (1 << 0) 138 #define DMAMAP_FROM_DMAMEM (1 << 1) 139 int sync_count; 140 struct sync_list slist[]; 141 }; 142 143 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 144 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 145 146 static void init_bounce_pages(void *dummy); 147 static int alloc_bounce_zone(bus_dma_tag_t dmat); 148 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 149 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 150 int commit); 151 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 152 vm_offset_t vaddr, bus_addr_t addr, bus_size_t size); 153 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 154 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 155 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 156 pmap_t pmap, void *buf, bus_size_t buflen, int flags); 157 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 158 vm_paddr_t buf, bus_size_t buflen, int flags); 159 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 160 int flags); 161 162 /* 163 * Allocate a device specific dma_tag. 164 */ 165 static int 166 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 167 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr, 168 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize, 169 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 170 void *lockfuncarg, bus_dma_tag_t *dmat) 171 { 172 bus_dma_tag_t newtag; 173 int error; 174 175 *dmat = NULL; 176 error = common_bus_dma_tag_create(parent != NULL ? &parent->common : 177 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg, 178 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg, 179 sizeof (struct bus_dma_tag), (void **)&newtag); 180 if (error != 0) 181 return (error); 182 183 newtag->common.impl = &bus_dma_bounce_impl; 184 newtag->map_count = 0; 185 newtag->segments = NULL; 186 187 if ((flags & BUS_DMA_COHERENT) != 0) 188 newtag->bounce_flags |= BF_COHERENT; 189 190 if (parent != NULL) { 191 if ((newtag->common.filter != NULL || 192 (parent->bounce_flags & BF_COULD_BOUNCE) != 0)) 193 newtag->bounce_flags |= BF_COULD_BOUNCE; 194 195 /* Copy some flags from the parent */ 196 newtag->bounce_flags |= parent->bounce_flags & BF_COHERENT; 197 } 198 199 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) || 200 newtag->common.alignment > 1) 201 newtag->bounce_flags |= BF_COULD_BOUNCE; 202 203 if (((newtag->bounce_flags & BF_COULD_BOUNCE) != 0) && 204 (flags & BUS_DMA_ALLOCNOW) != 0) { 205 struct bounce_zone *bz; 206 207 /* Must bounce */ 208 if ((error = alloc_bounce_zone(newtag)) != 0) { 209 free(newtag, M_DEVBUF); 210 return (error); 211 } 212 bz = newtag->bounce_zone; 213 214 if (ptoa(bz->total_bpages) < maxsize) { 215 int pages; 216 217 pages = atop(round_page(maxsize)) - bz->total_bpages; 218 219 /* Add pages to our bounce pool */ 220 if (alloc_bounce_pages(newtag, pages) < pages) 221 error = ENOMEM; 222 } 223 /* Performed initial allocation */ 224 newtag->bounce_flags |= BF_MIN_ALLOC_COMP; 225 } else 226 error = 0; 227 228 if (error != 0) 229 free(newtag, M_DEVBUF); 230 else 231 *dmat = newtag; 232 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 233 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0), 234 error); 235 return (error); 236 } 237 238 static int 239 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat) 240 { 241 bus_dma_tag_t dmat_copy, parent; 242 int error; 243 244 error = 0; 245 dmat_copy = dmat; 246 247 if (dmat != NULL) { 248 if (dmat->map_count != 0) { 249 error = EBUSY; 250 goto out; 251 } 252 while (dmat != NULL) { 253 parent = (bus_dma_tag_t)dmat->common.parent; 254 atomic_subtract_int(&dmat->common.ref_count, 1); 255 if (dmat->common.ref_count == 0) { 256 if (dmat->segments != NULL) 257 free(dmat->segments, M_DEVBUF); 258 free(dmat, M_DEVBUF); 259 /* 260 * Last reference count, so 261 * release our reference 262 * count on our parent. 263 */ 264 dmat = parent; 265 } else 266 dmat = NULL; 267 } 268 } 269 out: 270 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 271 return (error); 272 } 273 274 static bus_dmamap_t 275 alloc_dmamap(bus_dma_tag_t dmat, int flags) 276 { 277 u_long mapsize; 278 bus_dmamap_t map; 279 280 mapsize = sizeof(*map); 281 mapsize += sizeof(struct sync_list) * dmat->common.nsegments; 282 map = malloc(mapsize, M_DEVBUF, flags | M_ZERO); 283 if (map == NULL) 284 return (NULL); 285 286 /* Initialize the new map */ 287 STAILQ_INIT(&map->bpages); 288 289 return (map); 290 } 291 292 /* 293 * Allocate a handle for mapping from kva/uva/physical 294 * address space into bus device space. 295 */ 296 static int 297 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 298 { 299 struct bounce_zone *bz; 300 int error, maxpages, pages; 301 302 error = 0; 303 304 if (dmat->segments == NULL) { 305 dmat->segments = (bus_dma_segment_t *)malloc( 306 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 307 M_DEVBUF, M_NOWAIT); 308 if (dmat->segments == NULL) { 309 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 310 __func__, dmat, ENOMEM); 311 return (ENOMEM); 312 } 313 } 314 315 *mapp = alloc_dmamap(dmat, M_NOWAIT); 316 if (*mapp == NULL) { 317 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 318 __func__, dmat, ENOMEM); 319 return (ENOMEM); 320 } 321 322 /* 323 * Bouncing might be required if the driver asks for an active 324 * exclusion region, a data alignment that is stricter than 1, and/or 325 * an active address boundary. 326 */ 327 if (dmat->bounce_flags & BF_COULD_BOUNCE) { 328 /* Must bounce */ 329 if (dmat->bounce_zone == NULL) { 330 if ((error = alloc_bounce_zone(dmat)) != 0) { 331 free(*mapp, M_DEVBUF); 332 return (error); 333 } 334 } 335 bz = dmat->bounce_zone; 336 337 (*mapp)->flags = DMAMAP_COULD_BOUNCE; 338 339 /* 340 * Attempt to add pages to our pool on a per-instance 341 * basis up to a sane limit. 342 */ 343 if (dmat->common.alignment > 1) 344 maxpages = MAX_BPAGES; 345 else 346 maxpages = MIN(MAX_BPAGES, Maxmem - 347 atop(dmat->common.lowaddr)); 348 if ((dmat->bounce_flags & BF_MIN_ALLOC_COMP) == 0 || 349 (bz->map_count > 0 && bz->total_bpages < maxpages)) { 350 pages = MAX(atop(dmat->common.maxsize), 1); 351 pages = MIN(maxpages - bz->total_bpages, pages); 352 pages = MAX(pages, 1); 353 if (alloc_bounce_pages(dmat, pages) < pages) 354 error = ENOMEM; 355 if ((dmat->bounce_flags & BF_MIN_ALLOC_COMP) 356 == 0) { 357 if (error == 0) { 358 dmat->bounce_flags |= 359 BF_MIN_ALLOC_COMP; 360 } 361 } else 362 error = 0; 363 } 364 bz->map_count++; 365 } 366 if (error == 0) 367 dmat->map_count++; 368 else 369 free(*mapp, M_DEVBUF); 370 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 371 __func__, dmat, dmat->common.flags, error); 372 return (error); 373 } 374 375 /* 376 * Destroy a handle for mapping from kva/uva/physical 377 * address space into bus device space. 378 */ 379 static int 380 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 381 { 382 383 /* Check we are destroying the correct map type */ 384 if ((map->flags & DMAMAP_FROM_DMAMEM) != 0) 385 panic("bounce_bus_dmamap_destroy: Invalid map freed\n"); 386 387 if (STAILQ_FIRST(&map->bpages) != NULL || map->sync_count != 0) { 388 CTR3(KTR_BUSDMA, "%s: tag %p error %d", __func__, dmat, EBUSY); 389 return (EBUSY); 390 } 391 if (dmat->bounce_zone) { 392 KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0, 393 ("%s: Bounce zone when cannot bounce", __func__)); 394 dmat->bounce_zone->map_count--; 395 } 396 free(map, M_DEVBUF); 397 dmat->map_count--; 398 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 399 return (0); 400 } 401 402 403 /* 404 * Allocate a piece of memory that can be efficiently mapped into 405 * bus device space based on the constraints lited in the dma tag. 406 * A dmamap to for use with dmamap_load is also allocated. 407 */ 408 static int 409 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 410 bus_dmamap_t *mapp) 411 { 412 /* 413 * XXX ARM64TODO: 414 * This bus_dma implementation requires IO-Coherent architecutre. 415 * If IO-Coherency is not guaranteed, the BUS_DMA_COHERENT flag has 416 * to be implented using non-cacheable memory. 417 */ 418 419 vm_memattr_t attr; 420 int mflags; 421 422 if (flags & BUS_DMA_NOWAIT) 423 mflags = M_NOWAIT; 424 else 425 mflags = M_WAITOK; 426 427 if (dmat->segments == NULL) { 428 dmat->segments = (bus_dma_segment_t *)malloc( 429 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 430 M_DEVBUF, mflags); 431 if (dmat->segments == NULL) { 432 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 433 __func__, dmat, dmat->common.flags, ENOMEM); 434 return (ENOMEM); 435 } 436 } 437 if (flags & BUS_DMA_ZERO) 438 mflags |= M_ZERO; 439 if (flags & BUS_DMA_NOCACHE) 440 attr = VM_MEMATTR_UNCACHEABLE; 441 else if ((flags & BUS_DMA_COHERENT) != 0 && 442 (dmat->bounce_flags & BF_COHERENT) == 0) 443 /* 444 * If we have a non-coherent tag, and are trying to allocate 445 * a coherent block of memory it needs to be uncached. 446 */ 447 attr = VM_MEMATTR_UNCACHEABLE; 448 else 449 attr = VM_MEMATTR_DEFAULT; 450 451 /* 452 * Create the map, but don't set the could bounce flag as 453 * this allocation should never bounce; 454 */ 455 *mapp = alloc_dmamap(dmat, mflags); 456 if (*mapp == NULL) { 457 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 458 __func__, dmat, dmat->common.flags, ENOMEM); 459 return (ENOMEM); 460 } 461 (*mapp)->flags = DMAMAP_FROM_DMAMEM; 462 463 /* 464 * Allocate the buffer from the malloc(9) allocator if... 465 * - It's small enough to fit into a single power of two sized bucket. 466 * - The alignment is less than or equal to the maximum size 467 * - The low address requirement is fulfilled. 468 * else allocate non-contiguous pages if... 469 * - The page count that could get allocated doesn't exceed 470 * nsegments also when the maximum segment size is less 471 * than PAGE_SIZE. 472 * - The alignment constraint isn't larger than a page boundary. 473 * - There are no boundary-crossing constraints. 474 * else allocate a block of contiguous pages because one or more of the 475 * constraints is something that only the contig allocator can fulfill. 476 * 477 * NOTE: The (dmat->common.alignment <= dmat->maxsize) check 478 * below is just a quick hack. The exact alignment guarantees 479 * of malloc(9) need to be nailed down, and the code below 480 * should be rewritten to take that into account. 481 * 482 * In the meantime warn the user if malloc gets it wrong. 483 */ 484 if ((dmat->common.maxsize <= PAGE_SIZE) && 485 (dmat->common.alignment <= dmat->common.maxsize) && 486 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) && 487 attr == VM_MEMATTR_DEFAULT) { 488 *vaddr = malloc(dmat->common.maxsize, M_DEVBUF, mflags); 489 } else if (dmat->common.nsegments >= 490 howmany(dmat->common.maxsize, MIN(dmat->common.maxsegsz, PAGE_SIZE)) && 491 dmat->common.alignment <= PAGE_SIZE && 492 (dmat->common.boundary % PAGE_SIZE) == 0) { 493 /* Page-based multi-segment allocations allowed */ 494 *vaddr = (void *)kmem_alloc_attr(dmat->common.maxsize, mflags, 495 0ul, dmat->common.lowaddr, attr); 496 dmat->bounce_flags |= BF_KMEM_ALLOC; 497 } else { 498 *vaddr = (void *)kmem_alloc_contig(dmat->common.maxsize, mflags, 499 0ul, dmat->common.lowaddr, dmat->common.alignment != 0 ? 500 dmat->common.alignment : 1ul, dmat->common.boundary, attr); 501 dmat->bounce_flags |= BF_KMEM_ALLOC; 502 } 503 if (*vaddr == NULL) { 504 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 505 __func__, dmat, dmat->common.flags, ENOMEM); 506 free(*mapp, M_DEVBUF); 507 return (ENOMEM); 508 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) { 509 printf("bus_dmamem_alloc failed to align memory properly.\n"); 510 } 511 dmat->map_count++; 512 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 513 __func__, dmat, dmat->common.flags, 0); 514 return (0); 515 } 516 517 /* 518 * Free a piece of memory and it's allociated dmamap, that was allocated 519 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 520 */ 521 static void 522 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 523 { 524 525 /* 526 * Check the map came from bounce_bus_dmamem_alloc, so the map 527 * should be NULL and the BF_KMEM_ALLOC flag cleared if malloc() 528 * was used and set if kmem_alloc_contig() was used. 529 */ 530 if ((map->flags & DMAMAP_FROM_DMAMEM) == 0) 531 panic("bus_dmamem_free: Invalid map freed\n"); 532 if ((dmat->bounce_flags & BF_KMEM_ALLOC) == 0) 533 free(vaddr, M_DEVBUF); 534 else 535 kmem_free((vm_offset_t)vaddr, dmat->common.maxsize); 536 free(map, M_DEVBUF); 537 dmat->map_count--; 538 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, 539 dmat->bounce_flags); 540 } 541 542 static void 543 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 544 bus_size_t buflen, int flags) 545 { 546 bus_addr_t curaddr; 547 bus_size_t sgsize; 548 549 if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) { 550 /* 551 * Count the number of bounce pages 552 * needed in order to complete this transfer 553 */ 554 curaddr = buf; 555 while (buflen != 0) { 556 sgsize = MIN(buflen, dmat->common.maxsegsz); 557 if (bus_dma_run_filter(&dmat->common, curaddr)) { 558 sgsize = MIN(sgsize, 559 PAGE_SIZE - (curaddr & PAGE_MASK)); 560 map->pagesneeded++; 561 } 562 curaddr += sgsize; 563 buflen -= sgsize; 564 } 565 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 566 } 567 } 568 569 static void 570 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 571 void *buf, bus_size_t buflen, int flags) 572 { 573 vm_offset_t vaddr; 574 vm_offset_t vendaddr; 575 bus_addr_t paddr; 576 bus_size_t sg_len; 577 578 if ((map->flags & DMAMAP_COULD_BOUNCE) != 0 && map->pagesneeded == 0) { 579 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 580 "alignment= %d", dmat->common.lowaddr, 581 ptoa((vm_paddr_t)Maxmem), 582 dmat->common.boundary, dmat->common.alignment); 583 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, 584 map->pagesneeded); 585 /* 586 * Count the number of bounce pages 587 * needed in order to complete this transfer 588 */ 589 vaddr = (vm_offset_t)buf; 590 vendaddr = (vm_offset_t)buf + buflen; 591 592 while (vaddr < vendaddr) { 593 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 594 if (pmap == kernel_pmap) 595 paddr = pmap_kextract(vaddr); 596 else 597 paddr = pmap_extract(pmap, vaddr); 598 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 599 sg_len = roundup2(sg_len, 600 dmat->common.alignment); 601 map->pagesneeded++; 602 } 603 vaddr += sg_len; 604 } 605 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 606 } 607 } 608 609 static int 610 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 611 { 612 613 /* Reserve Necessary Bounce Pages */ 614 mtx_lock(&bounce_lock); 615 if (flags & BUS_DMA_NOWAIT) { 616 if (reserve_bounce_pages(dmat, map, 0) != 0) { 617 mtx_unlock(&bounce_lock); 618 return (ENOMEM); 619 } 620 } else { 621 if (reserve_bounce_pages(dmat, map, 1) != 0) { 622 /* Queue us for resources */ 623 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 624 mtx_unlock(&bounce_lock); 625 return (EINPROGRESS); 626 } 627 } 628 mtx_unlock(&bounce_lock); 629 630 return (0); 631 } 632 633 /* 634 * Add a single contiguous physical range to the segment list. 635 */ 636 static int 637 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr, 638 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 639 { 640 bus_addr_t baddr, bmask; 641 int seg; 642 643 /* 644 * Make sure we don't cross any boundaries. 645 */ 646 bmask = ~(dmat->common.boundary - 1); 647 if (dmat->common.boundary > 0) { 648 baddr = (curaddr + dmat->common.boundary) & bmask; 649 if (sgsize > (baddr - curaddr)) 650 sgsize = (baddr - curaddr); 651 } 652 653 /* 654 * Insert chunk into a segment, coalescing with 655 * previous segment if possible. 656 */ 657 seg = *segp; 658 if (seg == -1) { 659 seg = 0; 660 segs[seg].ds_addr = curaddr; 661 segs[seg].ds_len = sgsize; 662 } else { 663 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 664 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz && 665 (dmat->common.boundary == 0 || 666 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 667 segs[seg].ds_len += sgsize; 668 else { 669 if (++seg >= dmat->common.nsegments) 670 return (0); 671 segs[seg].ds_addr = curaddr; 672 segs[seg].ds_len = sgsize; 673 } 674 } 675 *segp = seg; 676 return (sgsize); 677 } 678 679 /* 680 * Utility function to load a physical buffer. segp contains 681 * the starting segment on entrace, and the ending segment on exit. 682 */ 683 static int 684 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 685 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, 686 int *segp) 687 { 688 struct sync_list *sl; 689 bus_size_t sgsize; 690 bus_addr_t curaddr, sl_end; 691 int error; 692 693 if (segs == NULL) 694 segs = dmat->segments; 695 696 if ((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) { 697 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 698 if (map->pagesneeded != 0) { 699 error = _bus_dmamap_reserve_pages(dmat, map, flags); 700 if (error) 701 return (error); 702 } 703 } 704 705 sl = map->slist + map->sync_count - 1; 706 sl_end = 0; 707 708 while (buflen > 0) { 709 curaddr = buf; 710 sgsize = MIN(buflen, dmat->common.maxsegsz); 711 if (((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) && 712 map->pagesneeded != 0 && 713 bus_dma_run_filter(&dmat->common, curaddr)) { 714 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK)); 715 curaddr = add_bounce_page(dmat, map, 0, curaddr, 716 sgsize); 717 } else if ((dmat->bounce_flags & BF_COHERENT) == 0) { 718 if (map->sync_count > 0) 719 sl_end = sl->paddr + sl->datacount; 720 721 if (map->sync_count == 0 || curaddr != sl_end) { 722 if (++map->sync_count > dmat->common.nsegments) 723 break; 724 sl++; 725 sl->vaddr = 0; 726 sl->paddr = curaddr; 727 sl->datacount = sgsize; 728 sl->pages = PHYS_TO_VM_PAGE(curaddr); 729 KASSERT(sl->pages != NULL, 730 ("%s: page at PA:0x%08lx is not in " 731 "vm_page_array", __func__, curaddr)); 732 } else 733 sl->datacount += sgsize; 734 } 735 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 736 segp); 737 if (sgsize == 0) 738 break; 739 buf += sgsize; 740 buflen -= sgsize; 741 } 742 743 /* 744 * Did we fit? 745 */ 746 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 747 } 748 749 /* 750 * Utility function to load a linear buffer. segp contains 751 * the starting segment on entrace, and the ending segment on exit. 752 */ 753 static int 754 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 755 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, 756 int *segp) 757 { 758 struct sync_list *sl; 759 bus_size_t sgsize, max_sgsize; 760 bus_addr_t curaddr, sl_pend; 761 vm_offset_t kvaddr, vaddr, sl_vend; 762 int error; 763 764 if (segs == NULL) 765 segs = dmat->segments; 766 767 if ((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) { 768 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 769 if (map->pagesneeded != 0) { 770 error = _bus_dmamap_reserve_pages(dmat, map, flags); 771 if (error) 772 return (error); 773 } 774 } 775 776 sl = map->slist + map->sync_count - 1; 777 vaddr = (vm_offset_t)buf; 778 sl_pend = 0; 779 sl_vend = 0; 780 781 while (buflen > 0) { 782 /* 783 * Get the physical address for this segment. 784 */ 785 if (pmap == kernel_pmap) { 786 curaddr = pmap_kextract(vaddr); 787 kvaddr = vaddr; 788 } else { 789 curaddr = pmap_extract(pmap, vaddr); 790 kvaddr = 0; 791 } 792 793 /* 794 * Compute the segment size, and adjust counts. 795 */ 796 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 797 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK); 798 if (((dmat->bounce_flags & BF_COULD_BOUNCE) != 0) && 799 map->pagesneeded != 0 && 800 bus_dma_run_filter(&dmat->common, curaddr)) { 801 sgsize = roundup2(sgsize, dmat->common.alignment); 802 sgsize = MIN(sgsize, max_sgsize); 803 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr, 804 sgsize); 805 } else if ((dmat->bounce_flags & BF_COHERENT) == 0) { 806 sgsize = MIN(sgsize, max_sgsize); 807 if (map->sync_count > 0) { 808 sl_pend = sl->paddr + sl->datacount; 809 sl_vend = sl->vaddr + sl->datacount; 810 } 811 812 if (map->sync_count == 0 || 813 (kvaddr != 0 && kvaddr != sl_vend) || 814 (curaddr != sl_pend)) { 815 816 if (++map->sync_count > dmat->common.nsegments) 817 goto cleanup; 818 sl++; 819 sl->vaddr = kvaddr; 820 sl->paddr = curaddr; 821 if (kvaddr != 0) { 822 sl->pages = NULL; 823 } else { 824 sl->pages = PHYS_TO_VM_PAGE(curaddr); 825 KASSERT(sl->pages != NULL, 826 ("%s: page at PA:0x%08lx is not " 827 "in vm_page_array", __func__, 828 curaddr)); 829 } 830 sl->datacount = sgsize; 831 } else 832 sl->datacount += sgsize; 833 } else { 834 sgsize = MIN(sgsize, max_sgsize); 835 } 836 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 837 segp); 838 if (sgsize == 0) 839 break; 840 vaddr += sgsize; 841 buflen -= sgsize; 842 } 843 844 cleanup: 845 /* 846 * Did we fit? 847 */ 848 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 849 } 850 851 static void 852 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 853 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) 854 { 855 856 if ((map->flags & DMAMAP_COULD_BOUNCE) == 0) 857 return; 858 map->mem = *mem; 859 map->dmat = dmat; 860 map->callback = callback; 861 map->callback_arg = callback_arg; 862 } 863 864 static bus_dma_segment_t * 865 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 866 bus_dma_segment_t *segs, int nsegs, int error) 867 { 868 869 if (segs == NULL) 870 segs = dmat->segments; 871 return (segs); 872 } 873 874 /* 875 * Release the mapping held by map. 876 */ 877 static void 878 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 879 { 880 struct bounce_page *bpage; 881 882 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 883 STAILQ_REMOVE_HEAD(&map->bpages, links); 884 free_bounce_page(dmat, bpage); 885 } 886 887 map->sync_count = 0; 888 } 889 890 static void 891 dma_preread_safe(vm_offset_t va, vm_size_t size) 892 { 893 /* 894 * Write back any partial cachelines immediately before and 895 * after the DMA region. 896 */ 897 if (va & (dcache_line_size - 1)) 898 cpu_dcache_wb_range(va, 1); 899 if ((va + size) & (dcache_line_size - 1)) 900 cpu_dcache_wb_range(va + size, 1); 901 902 cpu_dcache_inv_range(va, size); 903 } 904 905 static void 906 dma_dcache_sync(struct sync_list *sl, bus_dmasync_op_t op) 907 { 908 uint32_t len, offset; 909 vm_page_t m; 910 vm_paddr_t pa; 911 vm_offset_t va, tempva; 912 bus_size_t size; 913 914 offset = sl->paddr & PAGE_MASK; 915 m = sl->pages; 916 size = sl->datacount; 917 pa = sl->paddr; 918 919 for ( ; size != 0; size -= len, pa += len, offset = 0, ++m) { 920 tempva = 0; 921 if (sl->vaddr == 0) { 922 len = min(PAGE_SIZE - offset, size); 923 tempva = pmap_quick_enter_page(m); 924 va = tempva | offset; 925 KASSERT(pa == (VM_PAGE_TO_PHYS(m) | offset), 926 ("unexpected vm_page_t phys: 0x%16lx != 0x%16lx", 927 VM_PAGE_TO_PHYS(m) | offset, pa)); 928 } else { 929 len = sl->datacount; 930 va = sl->vaddr; 931 } 932 933 switch (op) { 934 case BUS_DMASYNC_PREWRITE: 935 case BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD: 936 cpu_dcache_wb_range(va, len); 937 break; 938 case BUS_DMASYNC_PREREAD: 939 /* 940 * An mbuf may start in the middle of a cacheline. There 941 * will be no cpu writes to the beginning of that line 942 * (which contains the mbuf header) while dma is in 943 * progress. Handle that case by doing a writeback of 944 * just the first cacheline before invalidating the 945 * overall buffer. Any mbuf in a chain may have this 946 * misalignment. Buffers which are not mbufs bounce if 947 * they are not aligned to a cacheline. 948 */ 949 dma_preread_safe(va, len); 950 break; 951 case BUS_DMASYNC_POSTREAD: 952 case BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE: 953 cpu_dcache_inv_range(va, len); 954 break; 955 default: 956 panic("unsupported combination of sync operations: " 957 "0x%08x\n", op); 958 } 959 960 if (tempva != 0) 961 pmap_quick_remove_page(tempva); 962 } 963 } 964 965 static void 966 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, 967 bus_dmasync_op_t op) 968 { 969 struct bounce_page *bpage; 970 struct sync_list *sl, *end; 971 vm_offset_t datavaddr, tempvaddr; 972 973 if (op == BUS_DMASYNC_POSTWRITE) 974 return; 975 976 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 977 /* 978 * Wait for any DMA operations to complete before the bcopy. 979 */ 980 fence(); 981 } 982 983 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 984 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 985 "performing bounce", __func__, dmat, dmat->common.flags, 986 op); 987 988 if ((op & BUS_DMASYNC_PREWRITE) != 0) { 989 while (bpage != NULL) { 990 tempvaddr = 0; 991 datavaddr = bpage->datavaddr; 992 if (datavaddr == 0) { 993 tempvaddr = pmap_quick_enter_page( 994 bpage->datapage); 995 datavaddr = tempvaddr | bpage->dataoffs; 996 } 997 998 bcopy((void *)datavaddr, 999 (void *)bpage->vaddr, bpage->datacount); 1000 if (tempvaddr != 0) 1001 pmap_quick_remove_page(tempvaddr); 1002 if ((dmat->bounce_flags & BF_COHERENT) == 0) 1003 cpu_dcache_wb_range(bpage->vaddr, 1004 bpage->datacount); 1005 bpage = STAILQ_NEXT(bpage, links); 1006 } 1007 dmat->bounce_zone->total_bounced++; 1008 } else if ((op & BUS_DMASYNC_PREREAD) != 0) { 1009 while (bpage != NULL) { 1010 if ((dmat->bounce_flags & BF_COHERENT) == 0) 1011 cpu_dcache_wbinv_range(bpage->vaddr, 1012 bpage->datacount); 1013 bpage = STAILQ_NEXT(bpage, links); 1014 } 1015 } 1016 1017 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 1018 while (bpage != NULL) { 1019 if ((dmat->bounce_flags & BF_COHERENT) == 0) 1020 cpu_dcache_inv_range(bpage->vaddr, 1021 bpage->datacount); 1022 tempvaddr = 0; 1023 datavaddr = bpage->datavaddr; 1024 if (datavaddr == 0) { 1025 tempvaddr = pmap_quick_enter_page( 1026 bpage->datapage); 1027 datavaddr = tempvaddr | bpage->dataoffs; 1028 } 1029 1030 bcopy((void *)bpage->vaddr, 1031 (void *)datavaddr, bpage->datacount); 1032 1033 if (tempvaddr != 0) 1034 pmap_quick_remove_page(tempvaddr); 1035 bpage = STAILQ_NEXT(bpage, links); 1036 } 1037 dmat->bounce_zone->total_bounced++; 1038 } 1039 } 1040 1041 /* 1042 * Cache maintenance for normal (non-COHERENT non-bounce) buffers. 1043 */ 1044 if (map->sync_count != 0) { 1045 sl = &map->slist[0]; 1046 end = &map->slist[map->sync_count]; 1047 CTR3(KTR_BUSDMA, "%s: tag %p op 0x%x " 1048 "performing sync", __func__, dmat, op); 1049 1050 for ( ; sl != end; ++sl) 1051 dma_dcache_sync(sl, op); 1052 } 1053 1054 if ((op & (BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE)) != 0) { 1055 /* 1056 * Wait for the bcopy to complete before any DMA operations. 1057 */ 1058 fence(); 1059 } 1060 } 1061 1062 static void 1063 init_bounce_pages(void *dummy __unused) 1064 { 1065 1066 total_bpages = 0; 1067 STAILQ_INIT(&bounce_zone_list); 1068 STAILQ_INIT(&bounce_map_waitinglist); 1069 STAILQ_INIT(&bounce_map_callbacklist); 1070 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 1071 } 1072 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 1073 1074 static struct sysctl_ctx_list * 1075 busdma_sysctl_tree(struct bounce_zone *bz) 1076 { 1077 1078 return (&bz->sysctl_tree); 1079 } 1080 1081 static struct sysctl_oid * 1082 busdma_sysctl_tree_top(struct bounce_zone *bz) 1083 { 1084 1085 return (bz->sysctl_tree_top); 1086 } 1087 1088 static int 1089 alloc_bounce_zone(bus_dma_tag_t dmat) 1090 { 1091 struct bounce_zone *bz; 1092 1093 /* Check to see if we already have a suitable zone */ 1094 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1095 if ((dmat->common.alignment <= bz->alignment) && 1096 (dmat->common.lowaddr >= bz->lowaddr)) { 1097 dmat->bounce_zone = bz; 1098 return (0); 1099 } 1100 } 1101 1102 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1103 M_NOWAIT | M_ZERO)) == NULL) 1104 return (ENOMEM); 1105 1106 STAILQ_INIT(&bz->bounce_page_list); 1107 bz->free_bpages = 0; 1108 bz->reserved_bpages = 0; 1109 bz->active_bpages = 0; 1110 bz->lowaddr = dmat->common.lowaddr; 1111 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE); 1112 bz->map_count = 0; 1113 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1114 busdma_zonecount++; 1115 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1116 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1117 dmat->bounce_zone = bz; 1118 1119 sysctl_ctx_init(&bz->sysctl_tree); 1120 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1121 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1122 CTLFLAG_RD, 0, ""); 1123 if (bz->sysctl_tree_top == NULL) { 1124 sysctl_ctx_free(&bz->sysctl_tree); 1125 return (0); /* XXX error code? */ 1126 } 1127 1128 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1129 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1130 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1131 "Total bounce pages"); 1132 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1133 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1134 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1135 "Free bounce pages"); 1136 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1137 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1138 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1139 "Reserved bounce pages"); 1140 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1141 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1142 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1143 "Active bounce pages"); 1144 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1145 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1146 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1147 "Total bounce requests"); 1148 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1149 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1150 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1151 "Total bounce requests that were deferred"); 1152 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1153 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1154 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1155 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz), 1156 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1157 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1158 1159 return (0); 1160 } 1161 1162 static int 1163 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1164 { 1165 struct bounce_zone *bz; 1166 int count; 1167 1168 bz = dmat->bounce_zone; 1169 count = 0; 1170 while (numpages > 0) { 1171 struct bounce_page *bpage; 1172 1173 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1174 M_NOWAIT | M_ZERO); 1175 1176 if (bpage == NULL) 1177 break; 1178 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1179 M_NOWAIT, 0ul, bz->lowaddr, PAGE_SIZE, 0); 1180 if (bpage->vaddr == 0) { 1181 free(bpage, M_DEVBUF); 1182 break; 1183 } 1184 bpage->busaddr = pmap_kextract(bpage->vaddr); 1185 mtx_lock(&bounce_lock); 1186 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1187 total_bpages++; 1188 bz->total_bpages++; 1189 bz->free_bpages++; 1190 mtx_unlock(&bounce_lock); 1191 count++; 1192 numpages--; 1193 } 1194 return (count); 1195 } 1196 1197 static int 1198 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1199 { 1200 struct bounce_zone *bz; 1201 int pages; 1202 1203 mtx_assert(&bounce_lock, MA_OWNED); 1204 bz = dmat->bounce_zone; 1205 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1206 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1207 return (map->pagesneeded - (map->pagesreserved + pages)); 1208 bz->free_bpages -= pages; 1209 bz->reserved_bpages += pages; 1210 map->pagesreserved += pages; 1211 pages = map->pagesneeded - map->pagesreserved; 1212 1213 return (pages); 1214 } 1215 1216 static bus_addr_t 1217 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1218 bus_addr_t addr, bus_size_t size) 1219 { 1220 struct bounce_zone *bz; 1221 struct bounce_page *bpage; 1222 1223 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1224 KASSERT((map->flags & DMAMAP_COULD_BOUNCE) != 0, 1225 ("add_bounce_page: bad map %p", map)); 1226 1227 bz = dmat->bounce_zone; 1228 if (map->pagesneeded == 0) 1229 panic("add_bounce_page: map doesn't need any pages"); 1230 map->pagesneeded--; 1231 1232 if (map->pagesreserved == 0) 1233 panic("add_bounce_page: map doesn't need any pages"); 1234 map->pagesreserved--; 1235 1236 mtx_lock(&bounce_lock); 1237 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1238 if (bpage == NULL) 1239 panic("add_bounce_page: free page list is empty"); 1240 1241 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1242 bz->reserved_bpages--; 1243 bz->active_bpages++; 1244 mtx_unlock(&bounce_lock); 1245 1246 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1247 /* Page offset needs to be preserved. */ 1248 bpage->vaddr |= addr & PAGE_MASK; 1249 bpage->busaddr |= addr & PAGE_MASK; 1250 } 1251 bpage->datavaddr = vaddr; 1252 bpage->datapage = PHYS_TO_VM_PAGE(addr); 1253 bpage->dataoffs = addr & PAGE_MASK; 1254 bpage->datacount = size; 1255 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1256 return (bpage->busaddr); 1257 } 1258 1259 static void 1260 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1261 { 1262 struct bus_dmamap *map; 1263 struct bounce_zone *bz; 1264 1265 bz = dmat->bounce_zone; 1266 bpage->datavaddr = 0; 1267 bpage->datacount = 0; 1268 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1269 /* 1270 * Reset the bounce page to start at offset 0. Other uses 1271 * of this bounce page may need to store a full page of 1272 * data and/or assume it starts on a page boundary. 1273 */ 1274 bpage->vaddr &= ~PAGE_MASK; 1275 bpage->busaddr &= ~PAGE_MASK; 1276 } 1277 1278 mtx_lock(&bounce_lock); 1279 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1280 bz->free_bpages++; 1281 bz->active_bpages--; 1282 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1283 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1284 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1285 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1286 map, links); 1287 busdma_swi_pending = 1; 1288 bz->total_deferred++; 1289 swi_sched(vm_ih, 0); 1290 } 1291 } 1292 mtx_unlock(&bounce_lock); 1293 } 1294 1295 void 1296 busdma_swi(void) 1297 { 1298 bus_dma_tag_t dmat; 1299 struct bus_dmamap *map; 1300 1301 mtx_lock(&bounce_lock); 1302 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1303 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1304 mtx_unlock(&bounce_lock); 1305 dmat = map->dmat; 1306 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK); 1307 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1308 map->callback, map->callback_arg, BUS_DMA_WAITOK); 1309 (dmat->common.lockfunc)(dmat->common.lockfuncarg, 1310 BUS_DMA_UNLOCK); 1311 mtx_lock(&bounce_lock); 1312 } 1313 mtx_unlock(&bounce_lock); 1314 } 1315 1316 struct bus_dma_impl bus_dma_bounce_impl = { 1317 .tag_create = bounce_bus_dma_tag_create, 1318 .tag_destroy = bounce_bus_dma_tag_destroy, 1319 .map_create = bounce_bus_dmamap_create, 1320 .map_destroy = bounce_bus_dmamap_destroy, 1321 .mem_alloc = bounce_bus_dmamem_alloc, 1322 .mem_free = bounce_bus_dmamem_free, 1323 .load_phys = bounce_bus_dmamap_load_phys, 1324 .load_buffer = bounce_bus_dmamap_load_buffer, 1325 .load_ma = bus_dmamap_load_ma_triv, 1326 .map_waitok = bounce_bus_dmamap_waitok, 1327 .map_complete = bounce_bus_dmamap_complete, 1328 .map_unload = bounce_bus_dmamap_unload, 1329 .map_sync = bounce_bus_dmamap_sync 1330 }; 1331