1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1997, 1998 Justin T. Gibbs. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions, and the following disclaimer, 12 * without modification, immediately at the beginning of the file. 13 * 2. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 20 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/malloc.h> 35 #include <sys/bus.h> 36 #include <sys/interrupt.h> 37 #include <sys/kernel.h> 38 #include <sys/ktr.h> 39 #include <sys/lock.h> 40 #include <sys/proc.h> 41 #include <sys/memdesc.h> 42 #include <sys/mutex.h> 43 #include <sys/sysctl.h> 44 #include <sys/uio.h> 45 46 #include <vm/vm.h> 47 #include <vm/vm_extern.h> 48 #include <vm/vm_kern.h> 49 #include <vm/vm_page.h> 50 #include <vm/vm_map.h> 51 52 #include <machine/atomic.h> 53 #include <machine/bus.h> 54 #include <machine/md_var.h> 55 #include <machine/specialreg.h> 56 #include <x86/include/busdma_impl.h> 57 58 #ifdef __i386__ 59 #define MAX_BPAGES 512 60 #else 61 #define MAX_BPAGES 8192 62 #endif 63 64 enum { 65 BUS_DMA_COULD_BOUNCE = 0x01, 66 BUS_DMA_MIN_ALLOC_COMP = 0x02, 67 BUS_DMA_KMEM_ALLOC = 0x04, 68 }; 69 70 struct bounce_zone; 71 72 struct bus_dma_tag { 73 struct bus_dma_tag_common common; 74 int map_count; 75 int bounce_flags; 76 bus_dma_segment_t *segments; 77 struct bounce_zone *bounce_zone; 78 }; 79 80 struct bounce_page { 81 vm_offset_t vaddr; /* kva of bounce buffer */ 82 bus_addr_t busaddr; /* Physical address */ 83 vm_offset_t datavaddr; /* kva of client data */ 84 vm_offset_t dataoffs; /* page offset of client data */ 85 vm_page_t datapage[2]; /* physical page(s) of client data */ 86 bus_size_t datacount; /* client data count */ 87 STAILQ_ENTRY(bounce_page) links; 88 }; 89 90 int busdma_swi_pending; 91 92 struct 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 int map_count; 102 int domain; 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 bus_dmamap { 121 struct bp_list bpages; 122 int pagesneeded; 123 int pagesreserved; 124 bus_dma_tag_t dmat; 125 struct memdesc mem; 126 bus_dmamap_callback_t *callback; 127 void *callback_arg; 128 STAILQ_ENTRY(bus_dmamap) links; 129 }; 130 131 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 132 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 133 static struct bus_dmamap nobounce_dmamap; 134 135 static void init_bounce_pages(void *dummy); 136 static int alloc_bounce_zone(bus_dma_tag_t dmat); 137 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 138 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 139 int commit); 140 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 141 vm_offset_t vaddr, bus_addr_t addr1, 142 bus_addr_t addr2, bus_size_t size); 143 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 144 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 145 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 146 pmap_t pmap, void *buf, bus_size_t buflen, 147 int flags); 148 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 149 vm_paddr_t buf, bus_size_t buflen, 150 int flags); 151 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 152 int flags); 153 154 static int 155 bounce_bus_dma_zone_setup(bus_dma_tag_t dmat) 156 { 157 struct bounce_zone *bz; 158 int error; 159 160 /* Must bounce */ 161 if ((error = alloc_bounce_zone(dmat)) != 0) 162 return (error); 163 bz = dmat->bounce_zone; 164 165 if (ptoa(bz->total_bpages) < dmat->common.maxsize) { 166 int pages; 167 168 pages = atop(dmat->common.maxsize) - bz->total_bpages; 169 170 /* Add pages to our bounce pool */ 171 if (alloc_bounce_pages(dmat, pages) < pages) 172 return (ENOMEM); 173 } 174 /* Performed initial allocation */ 175 dmat->bounce_flags |= BUS_DMA_MIN_ALLOC_COMP; 176 177 return (0); 178 } 179 180 /* 181 * Allocate a device specific dma_tag. 182 */ 183 static int 184 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 185 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr, 186 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize, 187 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 188 void *lockfuncarg, bus_dma_tag_t *dmat) 189 { 190 bus_dma_tag_t newtag; 191 int error; 192 193 *dmat = NULL; 194 error = common_bus_dma_tag_create(parent != NULL ? &parent->common : 195 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg, 196 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg, 197 sizeof (struct bus_dma_tag), (void **)&newtag); 198 if (error != 0) 199 return (error); 200 201 newtag->common.impl = &bus_dma_bounce_impl; 202 newtag->map_count = 0; 203 newtag->segments = NULL; 204 205 if (parent != NULL && ((newtag->common.filter != NULL) || 206 ((parent->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0))) 207 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE; 208 209 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) || 210 newtag->common.alignment > 1) 211 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE; 212 213 if (((newtag->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) && 214 (flags & BUS_DMA_ALLOCNOW) != 0) 215 error = bounce_bus_dma_zone_setup(newtag); 216 else 217 error = 0; 218 219 if (error != 0) 220 free(newtag, M_DEVBUF); 221 else 222 *dmat = newtag; 223 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 224 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0), 225 error); 226 return (error); 227 } 228 229 /* 230 * Update the domain for the tag. We may need to reallocate the zone and 231 * bounce pages. 232 */ 233 static int 234 bounce_bus_dma_tag_set_domain(bus_dma_tag_t dmat) 235 { 236 237 KASSERT(dmat->map_count == 0, 238 ("bounce_bus_dma_tag_set_domain: Domain set after use.\n")); 239 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) == 0 || 240 dmat->bounce_zone == NULL) 241 return (0); 242 dmat->bounce_flags &= ~BUS_DMA_MIN_ALLOC_COMP; 243 return (bounce_bus_dma_zone_setup(dmat)); 244 } 245 246 static int 247 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat) 248 { 249 bus_dma_tag_t dmat_copy, parent; 250 int error; 251 252 error = 0; 253 dmat_copy = dmat; 254 255 if (dmat != NULL) { 256 if (dmat->map_count != 0) { 257 error = EBUSY; 258 goto out; 259 } 260 while (dmat != NULL) { 261 parent = (bus_dma_tag_t)dmat->common.parent; 262 atomic_subtract_int(&dmat->common.ref_count, 1); 263 if (dmat->common.ref_count == 0) { 264 if (dmat->segments != NULL) 265 free_domain(dmat->segments, M_DEVBUF); 266 free(dmat, M_DEVBUF); 267 /* 268 * Last reference count, so 269 * release our reference 270 * count on our parent. 271 */ 272 dmat = parent; 273 } else 274 dmat = NULL; 275 } 276 } 277 out: 278 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 279 return (error); 280 } 281 282 /* 283 * Allocate a handle for mapping from kva/uva/physical 284 * address space into bus device space. 285 */ 286 static int 287 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 288 { 289 struct bounce_zone *bz; 290 int error, maxpages, pages; 291 292 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s", __func__); 293 294 error = 0; 295 296 if (dmat->segments == NULL) { 297 dmat->segments = (bus_dma_segment_t *)malloc_domain( 298 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 299 M_DEVBUF, dmat->common.domain, M_NOWAIT); 300 if (dmat->segments == NULL) { 301 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 302 __func__, dmat, ENOMEM); 303 return (ENOMEM); 304 } 305 } 306 307 /* 308 * Bouncing might be required if the driver asks for an active 309 * exclusion region, a data alignment that is stricter than 1, and/or 310 * an active address boundary. 311 */ 312 if (dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) { 313 /* Must bounce */ 314 if (dmat->bounce_zone == NULL) { 315 if ((error = alloc_bounce_zone(dmat)) != 0) 316 return (error); 317 } 318 bz = dmat->bounce_zone; 319 320 *mapp = (bus_dmamap_t)malloc_domain(sizeof(**mapp), M_DEVBUF, 321 dmat->common.domain, M_NOWAIT | M_ZERO); 322 if (*mapp == NULL) { 323 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 324 __func__, dmat, ENOMEM); 325 return (ENOMEM); 326 } 327 328 /* Initialize the new map */ 329 STAILQ_INIT(&((*mapp)->bpages)); 330 331 /* 332 * Attempt to add pages to our pool on a per-instance 333 * basis up to a sane limit. 334 */ 335 if (dmat->common.alignment > 1) 336 maxpages = MAX_BPAGES; 337 else 338 maxpages = MIN(MAX_BPAGES, Maxmem - 339 atop(dmat->common.lowaddr)); 340 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) == 0 || 341 (bz->map_count > 0 && bz->total_bpages < maxpages)) { 342 pages = MAX(atop(dmat->common.maxsize), 1); 343 pages = MIN(maxpages - bz->total_bpages, pages); 344 pages = MAX(pages, 1); 345 if (alloc_bounce_pages(dmat, pages) < pages) 346 error = ENOMEM; 347 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) 348 == 0) { 349 if (error == 0) { 350 dmat->bounce_flags |= 351 BUS_DMA_MIN_ALLOC_COMP; 352 } 353 } else 354 error = 0; 355 } 356 bz->map_count++; 357 } else { 358 *mapp = NULL; 359 } 360 if (error == 0) 361 dmat->map_count++; 362 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 363 __func__, dmat, dmat->common.flags, error); 364 return (error); 365 } 366 367 /* 368 * Destroy a handle for mapping from kva/uva/physical 369 * address space into bus device space. 370 */ 371 static int 372 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 373 { 374 375 if (map != NULL && map != &nobounce_dmamap) { 376 if (STAILQ_FIRST(&map->bpages) != NULL) { 377 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 378 __func__, dmat, EBUSY); 379 return (EBUSY); 380 } 381 if (dmat->bounce_zone) 382 dmat->bounce_zone->map_count--; 383 free_domain(map, M_DEVBUF); 384 } 385 dmat->map_count--; 386 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 387 return (0); 388 } 389 390 391 /* 392 * Allocate a piece of memory that can be efficiently mapped into 393 * bus device space based on the constraints lited in the dma tag. 394 * A dmamap to for use with dmamap_load is also allocated. 395 */ 396 static int 397 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 398 bus_dmamap_t *mapp) 399 { 400 vm_memattr_t attr; 401 int mflags; 402 403 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s", __func__); 404 405 if (flags & BUS_DMA_NOWAIT) 406 mflags = M_NOWAIT; 407 else 408 mflags = M_WAITOK; 409 410 /* If we succeed, no mapping/bouncing will be required */ 411 *mapp = NULL; 412 413 if (dmat->segments == NULL) { 414 dmat->segments = (bus_dma_segment_t *)malloc_domain( 415 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 416 M_DEVBUF, dmat->common.domain, mflags); 417 if (dmat->segments == NULL) { 418 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 419 __func__, dmat, dmat->common.flags, ENOMEM); 420 return (ENOMEM); 421 } 422 } 423 if (flags & BUS_DMA_ZERO) 424 mflags |= M_ZERO; 425 if (flags & BUS_DMA_NOCACHE) 426 attr = VM_MEMATTR_UNCACHEABLE; 427 else 428 attr = VM_MEMATTR_DEFAULT; 429 430 /* 431 * Allocate the buffer from the malloc(9) allocator if... 432 * - It's small enough to fit into a single power of two sized bucket. 433 * - The alignment is less than or equal to the maximum size 434 * - The low address requirement is fulfilled. 435 * else allocate non-contiguous pages if... 436 * - The page count that could get allocated doesn't exceed 437 * nsegments also when the maximum segment size is less 438 * than PAGE_SIZE. 439 * - The alignment constraint isn't larger than a page boundary. 440 * - There are no boundary-crossing constraints. 441 * else allocate a block of contiguous pages because one or more of the 442 * constraints is something that only the contig allocator can fulfill. 443 * 444 * NOTE: The (dmat->common.alignment <= dmat->maxsize) check 445 * below is just a quick hack. The exact alignment guarantees 446 * of malloc(9) need to be nailed down, and the code below 447 * should be rewritten to take that into account. 448 * 449 * In the meantime warn the user if malloc gets it wrong. 450 */ 451 if ((dmat->common.maxsize <= PAGE_SIZE) && 452 (dmat->common.alignment <= dmat->common.maxsize) && 453 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) && 454 attr == VM_MEMATTR_DEFAULT) { 455 *vaddr = malloc_domain(dmat->common.maxsize, M_DEVBUF, 456 dmat->common.domain, mflags); 457 } else if (dmat->common.nsegments >= 458 howmany(dmat->common.maxsize, MIN(dmat->common.maxsegsz, PAGE_SIZE)) && 459 dmat->common.alignment <= PAGE_SIZE && 460 (dmat->common.boundary % PAGE_SIZE) == 0) { 461 /* Page-based multi-segment allocations allowed */ 462 *vaddr = (void *)kmem_alloc_attr_domain(dmat->common.domain, 463 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr, 464 attr); 465 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 466 } else { 467 *vaddr = (void *)kmem_alloc_contig_domain(dmat->common.domain, 468 dmat->common.maxsize, mflags, 0ul, dmat->common.lowaddr, 469 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul, 470 dmat->common.boundary, attr); 471 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 472 } 473 if (*vaddr == NULL) { 474 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 475 __func__, dmat, dmat->common.flags, ENOMEM); 476 return (ENOMEM); 477 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) { 478 printf("bus_dmamem_alloc failed to align memory properly.\n"); 479 } 480 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 481 __func__, dmat, dmat->common.flags, 0); 482 return (0); 483 } 484 485 /* 486 * Free a piece of memory and it's allociated dmamap, that was allocated 487 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 488 */ 489 static void 490 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 491 { 492 /* 493 * dmamem does not need to be bounced, so the map should be 494 * NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc() 495 * was used and set if kmem_alloc_contig() was used. 496 */ 497 if (map != NULL) 498 panic("bus_dmamem_free: Invalid map freed\n"); 499 if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0) 500 free_domain(vaddr, M_DEVBUF); 501 else 502 kmem_free(kernel_arena, (vm_offset_t)vaddr, 503 dmat->common.maxsize); 504 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, 505 dmat->bounce_flags); 506 } 507 508 static void 509 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 510 bus_size_t buflen, int flags) 511 { 512 bus_addr_t curaddr; 513 bus_size_t sgsize; 514 515 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 516 /* 517 * Count the number of bounce pages 518 * needed in order to complete this transfer 519 */ 520 curaddr = buf; 521 while (buflen != 0) { 522 sgsize = MIN(buflen, dmat->common.maxsegsz); 523 if (bus_dma_run_filter(&dmat->common, curaddr)) { 524 sgsize = MIN(sgsize, 525 PAGE_SIZE - (curaddr & PAGE_MASK)); 526 map->pagesneeded++; 527 } 528 curaddr += sgsize; 529 buflen -= sgsize; 530 } 531 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 532 } 533 } 534 535 static void 536 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 537 void *buf, bus_size_t buflen, int flags) 538 { 539 vm_offset_t vaddr; 540 vm_offset_t vendaddr; 541 bus_addr_t paddr; 542 bus_size_t sg_len; 543 544 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 545 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 546 "alignment= %d", dmat->common.lowaddr, 547 ptoa((vm_paddr_t)Maxmem), 548 dmat->common.boundary, dmat->common.alignment); 549 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 550 map, &nobounce_dmamap, map->pagesneeded); 551 /* 552 * Count the number of bounce pages 553 * needed in order to complete this transfer 554 */ 555 vaddr = (vm_offset_t)buf; 556 vendaddr = (vm_offset_t)buf + buflen; 557 558 while (vaddr < vendaddr) { 559 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 560 if (pmap == kernel_pmap) 561 paddr = pmap_kextract(vaddr); 562 else 563 paddr = pmap_extract(pmap, vaddr); 564 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 565 sg_len = roundup2(sg_len, 566 dmat->common.alignment); 567 map->pagesneeded++; 568 } 569 vaddr += sg_len; 570 } 571 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 572 } 573 } 574 575 static void 576 _bus_dmamap_count_ma(bus_dma_tag_t dmat, bus_dmamap_t map, struct vm_page **ma, 577 int ma_offs, bus_size_t buflen, int flags) 578 { 579 bus_size_t sg_len, max_sgsize; 580 int page_index; 581 vm_paddr_t paddr; 582 583 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 584 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 585 "alignment= %d", dmat->common.lowaddr, 586 ptoa((vm_paddr_t)Maxmem), 587 dmat->common.boundary, dmat->common.alignment); 588 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 589 map, &nobounce_dmamap, map->pagesneeded); 590 591 /* 592 * Count the number of bounce pages 593 * needed in order to complete this transfer 594 */ 595 page_index = 0; 596 while (buflen > 0) { 597 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 598 sg_len = PAGE_SIZE - ma_offs; 599 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 600 sg_len = MIN(sg_len, max_sgsize); 601 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 602 sg_len = roundup2(sg_len, 603 dmat->common.alignment); 604 sg_len = MIN(sg_len, max_sgsize); 605 KASSERT((sg_len & (dmat->common.alignment - 1)) 606 == 0, ("Segment size is not aligned")); 607 map->pagesneeded++; 608 } 609 if (((ma_offs + sg_len) & ~PAGE_MASK) != 0) 610 page_index++; 611 ma_offs = (ma_offs + sg_len) & PAGE_MASK; 612 KASSERT(buflen >= sg_len, 613 ("Segment length overruns original buffer")); 614 buflen -= sg_len; 615 } 616 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 617 } 618 } 619 620 static int 621 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 622 { 623 624 /* Reserve Necessary Bounce Pages */ 625 mtx_lock(&bounce_lock); 626 if (flags & BUS_DMA_NOWAIT) { 627 if (reserve_bounce_pages(dmat, map, 0) != 0) { 628 mtx_unlock(&bounce_lock); 629 return (ENOMEM); 630 } 631 } else { 632 if (reserve_bounce_pages(dmat, map, 1) != 0) { 633 /* Queue us for resources */ 634 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 635 mtx_unlock(&bounce_lock); 636 return (EINPROGRESS); 637 } 638 } 639 mtx_unlock(&bounce_lock); 640 641 return (0); 642 } 643 644 /* 645 * Add a single contiguous physical range to the segment list. 646 */ 647 static int 648 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr, 649 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 650 { 651 bus_addr_t baddr, bmask; 652 int seg; 653 654 /* 655 * Make sure we don't cross any boundaries. 656 */ 657 bmask = ~(dmat->common.boundary - 1); 658 if (dmat->common.boundary > 0) { 659 baddr = (curaddr + dmat->common.boundary) & bmask; 660 if (sgsize > (baddr - curaddr)) 661 sgsize = (baddr - curaddr); 662 } 663 664 /* 665 * Insert chunk into a segment, coalescing with 666 * previous segment if possible. 667 */ 668 seg = *segp; 669 if (seg == -1) { 670 seg = 0; 671 segs[seg].ds_addr = curaddr; 672 segs[seg].ds_len = sgsize; 673 } else { 674 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 675 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz && 676 (dmat->common.boundary == 0 || 677 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 678 segs[seg].ds_len += sgsize; 679 else { 680 if (++seg >= dmat->common.nsegments) 681 return (0); 682 segs[seg].ds_addr = curaddr; 683 segs[seg].ds_len = sgsize; 684 } 685 } 686 *segp = seg; 687 return (sgsize); 688 } 689 690 /* 691 * Utility function to load a physical buffer. segp contains 692 * the starting segment on entrace, and the ending segment on exit. 693 */ 694 static int 695 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 696 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, 697 int *segp) 698 { 699 bus_size_t sgsize; 700 bus_addr_t curaddr; 701 int error; 702 703 if (map == NULL) 704 map = &nobounce_dmamap; 705 706 if (segs == NULL) 707 segs = dmat->segments; 708 709 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 710 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 711 if (map->pagesneeded != 0) { 712 error = _bus_dmamap_reserve_pages(dmat, map, flags); 713 if (error) 714 return (error); 715 } 716 } 717 718 while (buflen > 0) { 719 curaddr = buf; 720 sgsize = MIN(buflen, dmat->common.maxsegsz); 721 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) && 722 map->pagesneeded != 0 && 723 bus_dma_run_filter(&dmat->common, curaddr)) { 724 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK)); 725 curaddr = add_bounce_page(dmat, map, 0, curaddr, 0, 726 sgsize); 727 } 728 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 729 segp); 730 if (sgsize == 0) 731 break; 732 buf += sgsize; 733 buflen -= sgsize; 734 } 735 736 /* 737 * Did we fit? 738 */ 739 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 740 } 741 742 /* 743 * Utility function to load a linear buffer. segp contains 744 * the starting segment on entrace, and the ending segment on exit. 745 */ 746 static int 747 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 748 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, 749 int *segp) 750 { 751 bus_size_t sgsize, max_sgsize; 752 bus_addr_t curaddr; 753 vm_offset_t kvaddr, vaddr; 754 int error; 755 756 if (map == NULL) 757 map = &nobounce_dmamap; 758 759 if (segs == NULL) 760 segs = dmat->segments; 761 762 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 763 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 764 if (map->pagesneeded != 0) { 765 error = _bus_dmamap_reserve_pages(dmat, map, flags); 766 if (error) 767 return (error); 768 } 769 } 770 771 vaddr = (vm_offset_t)buf; 772 while (buflen > 0) { 773 /* 774 * Get the physical address for this segment. 775 */ 776 if (pmap == kernel_pmap) { 777 curaddr = pmap_kextract(vaddr); 778 kvaddr = vaddr; 779 } else { 780 curaddr = pmap_extract(pmap, vaddr); 781 kvaddr = 0; 782 } 783 784 /* 785 * Compute the segment size, and adjust counts. 786 */ 787 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 788 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK); 789 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) && 790 map->pagesneeded != 0 && 791 bus_dma_run_filter(&dmat->common, curaddr)) { 792 sgsize = roundup2(sgsize, dmat->common.alignment); 793 sgsize = MIN(sgsize, max_sgsize); 794 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr, 0, 795 sgsize); 796 } else { 797 sgsize = MIN(sgsize, max_sgsize); 798 } 799 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 800 segp); 801 if (sgsize == 0) 802 break; 803 vaddr += sgsize; 804 buflen -= sgsize; 805 } 806 807 /* 808 * Did we fit? 809 */ 810 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 811 } 812 813 static int 814 bounce_bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map, 815 struct vm_page **ma, bus_size_t buflen, int ma_offs, int flags, 816 bus_dma_segment_t *segs, int *segp) 817 { 818 vm_paddr_t paddr, next_paddr; 819 int error, page_index; 820 bus_size_t sgsize, max_sgsize; 821 822 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 823 /* 824 * If we have to keep the offset of each page this function 825 * is not suitable, switch back to bus_dmamap_load_ma_triv 826 * which is going to do the right thing in this case. 827 */ 828 error = bus_dmamap_load_ma_triv(dmat, map, ma, buflen, ma_offs, 829 flags, segs, segp); 830 return (error); 831 } 832 833 if (map == NULL) 834 map = &nobounce_dmamap; 835 836 if (segs == NULL) 837 segs = dmat->segments; 838 839 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 840 _bus_dmamap_count_ma(dmat, map, ma, ma_offs, buflen, flags); 841 if (map->pagesneeded != 0) { 842 error = _bus_dmamap_reserve_pages(dmat, map, flags); 843 if (error) 844 return (error); 845 } 846 } 847 848 page_index = 0; 849 while (buflen > 0) { 850 /* 851 * Compute the segment size, and adjust counts. 852 */ 853 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 854 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 855 sgsize = PAGE_SIZE - ma_offs; 856 if (((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) && 857 map->pagesneeded != 0 && 858 bus_dma_run_filter(&dmat->common, paddr)) { 859 sgsize = roundup2(sgsize, dmat->common.alignment); 860 sgsize = MIN(sgsize, max_sgsize); 861 KASSERT((sgsize & (dmat->common.alignment - 1)) == 0, 862 ("Segment size is not aligned")); 863 /* 864 * Check if two pages of the user provided buffer 865 * are used. 866 */ 867 if ((ma_offs + sgsize) > PAGE_SIZE) 868 next_paddr = 869 VM_PAGE_TO_PHYS(ma[page_index + 1]); 870 else 871 next_paddr = 0; 872 paddr = add_bounce_page(dmat, map, 0, paddr, 873 next_paddr, sgsize); 874 } else { 875 sgsize = MIN(sgsize, max_sgsize); 876 } 877 sgsize = _bus_dmamap_addseg(dmat, map, paddr, sgsize, segs, 878 segp); 879 if (sgsize == 0) 880 break; 881 KASSERT(buflen >= sgsize, 882 ("Segment length overruns original buffer")); 883 buflen -= sgsize; 884 if (((ma_offs + sgsize) & ~PAGE_MASK) != 0) 885 page_index++; 886 ma_offs = (ma_offs + sgsize) & PAGE_MASK; 887 } 888 889 /* 890 * Did we fit? 891 */ 892 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 893 } 894 895 static void 896 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 897 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) 898 { 899 900 if (map == NULL) 901 return; 902 map->mem = *mem; 903 map->dmat = dmat; 904 map->callback = callback; 905 map->callback_arg = callback_arg; 906 } 907 908 static bus_dma_segment_t * 909 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 910 bus_dma_segment_t *segs, int nsegs, int error) 911 { 912 913 if (segs == NULL) 914 segs = dmat->segments; 915 return (segs); 916 } 917 918 /* 919 * Release the mapping held by map. 920 */ 921 static void 922 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 923 { 924 struct bounce_page *bpage; 925 926 if (map == NULL) 927 return; 928 929 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 930 STAILQ_REMOVE_HEAD(&map->bpages, links); 931 free_bounce_page(dmat, bpage); 932 } 933 } 934 935 static void 936 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, 937 bus_dmasync_op_t op) 938 { 939 struct bounce_page *bpage; 940 vm_offset_t datavaddr, tempvaddr; 941 bus_size_t datacount1, datacount2; 942 943 if (map == NULL || (bpage = STAILQ_FIRST(&map->bpages)) == NULL) 944 return; 945 946 /* 947 * Handle data bouncing. We might also want to add support for 948 * invalidating the caches on broken hardware. 949 */ 950 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 951 "performing bounce", __func__, dmat, dmat->common.flags, op); 952 953 if ((op & BUS_DMASYNC_PREWRITE) != 0) { 954 while (bpage != NULL) { 955 tempvaddr = 0; 956 datavaddr = bpage->datavaddr; 957 datacount1 = bpage->datacount; 958 if (datavaddr == 0) { 959 tempvaddr = 960 pmap_quick_enter_page(bpage->datapage[0]); 961 datavaddr = tempvaddr | bpage->dataoffs; 962 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 963 datacount1); 964 } 965 966 bcopy((void *)datavaddr, 967 (void *)bpage->vaddr, datacount1); 968 969 if (tempvaddr != 0) 970 pmap_quick_remove_page(tempvaddr); 971 972 if (bpage->datapage[1] == 0) { 973 KASSERT(datacount1 == bpage->datacount, 974 ("Mismatch between data size and provided memory space")); 975 goto next_w; 976 } 977 978 /* 979 * We are dealing with an unmapped buffer that expands 980 * over two pages. 981 */ 982 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 983 datacount2 = bpage->datacount - datacount1; 984 bcopy((void *)datavaddr, 985 (void *)(bpage->vaddr + datacount1), datacount2); 986 pmap_quick_remove_page(datavaddr); 987 988 next_w: 989 bpage = STAILQ_NEXT(bpage, links); 990 } 991 dmat->bounce_zone->total_bounced++; 992 } 993 994 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 995 while (bpage != NULL) { 996 tempvaddr = 0; 997 datavaddr = bpage->datavaddr; 998 datacount1 = bpage->datacount; 999 if (datavaddr == 0) { 1000 tempvaddr = 1001 pmap_quick_enter_page(bpage->datapage[0]); 1002 datavaddr = tempvaddr | bpage->dataoffs; 1003 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 1004 datacount1); 1005 } 1006 1007 bcopy((void *)bpage->vaddr, (void *)datavaddr, 1008 datacount1); 1009 1010 if (tempvaddr != 0) 1011 pmap_quick_remove_page(tempvaddr); 1012 1013 if (bpage->datapage[1] == 0) { 1014 KASSERT(datacount1 == bpage->datacount, 1015 ("Mismatch between data size and provided memory space")); 1016 goto next_r; 1017 } 1018 1019 /* 1020 * We are dealing with an unmapped buffer that expands 1021 * over two pages. 1022 */ 1023 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 1024 datacount2 = bpage->datacount - datacount1; 1025 bcopy((void *)(bpage->vaddr + datacount1), 1026 (void *)datavaddr, datacount2); 1027 pmap_quick_remove_page(datavaddr); 1028 1029 next_r: 1030 bpage = STAILQ_NEXT(bpage, links); 1031 } 1032 dmat->bounce_zone->total_bounced++; 1033 } 1034 } 1035 1036 static void 1037 init_bounce_pages(void *dummy __unused) 1038 { 1039 1040 total_bpages = 0; 1041 STAILQ_INIT(&bounce_zone_list); 1042 STAILQ_INIT(&bounce_map_waitinglist); 1043 STAILQ_INIT(&bounce_map_callbacklist); 1044 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 1045 } 1046 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 1047 1048 static struct sysctl_ctx_list * 1049 busdma_sysctl_tree(struct bounce_zone *bz) 1050 { 1051 1052 return (&bz->sysctl_tree); 1053 } 1054 1055 static struct sysctl_oid * 1056 busdma_sysctl_tree_top(struct bounce_zone *bz) 1057 { 1058 1059 return (bz->sysctl_tree_top); 1060 } 1061 1062 static int 1063 alloc_bounce_zone(bus_dma_tag_t dmat) 1064 { 1065 struct bounce_zone *bz; 1066 1067 /* Check to see if we already have a suitable zone */ 1068 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1069 if ((dmat->common.alignment <= bz->alignment) && 1070 (dmat->common.lowaddr >= bz->lowaddr) && 1071 (dmat->common.domain == bz->domain)) { 1072 dmat->bounce_zone = bz; 1073 return (0); 1074 } 1075 } 1076 1077 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1078 M_NOWAIT | M_ZERO)) == NULL) 1079 return (ENOMEM); 1080 1081 STAILQ_INIT(&bz->bounce_page_list); 1082 bz->free_bpages = 0; 1083 bz->reserved_bpages = 0; 1084 bz->active_bpages = 0; 1085 bz->lowaddr = dmat->common.lowaddr; 1086 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE); 1087 bz->map_count = 0; 1088 bz->domain = dmat->common.domain; 1089 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1090 busdma_zonecount++; 1091 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1092 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1093 dmat->bounce_zone = bz; 1094 1095 sysctl_ctx_init(&bz->sysctl_tree); 1096 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1097 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1098 CTLFLAG_RD, 0, ""); 1099 if (bz->sysctl_tree_top == NULL) { 1100 sysctl_ctx_free(&bz->sysctl_tree); 1101 return (0); /* XXX error code? */ 1102 } 1103 1104 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1105 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1106 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1107 "Total bounce pages"); 1108 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1109 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1110 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1111 "Free bounce pages"); 1112 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1113 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1114 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1115 "Reserved bounce pages"); 1116 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1117 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1118 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1119 "Active bounce pages"); 1120 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1121 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1122 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1123 "Total bounce requests"); 1124 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1125 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1126 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1127 "Total bounce requests that were deferred"); 1128 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1129 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1130 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1131 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz), 1132 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1133 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1134 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1135 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1136 "domain", CTLFLAG_RD, &bz->domain, 0, 1137 "memory domain"); 1138 1139 return (0); 1140 } 1141 1142 static int 1143 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1144 { 1145 struct bounce_zone *bz; 1146 int count; 1147 1148 bz = dmat->bounce_zone; 1149 count = 0; 1150 while (numpages > 0) { 1151 struct bounce_page *bpage; 1152 1153 bpage = (struct bounce_page *)malloc_domain(sizeof(*bpage), 1154 M_DEVBUF, dmat->common.domain, M_NOWAIT | M_ZERO); 1155 1156 if (bpage == NULL) 1157 break; 1158 bpage->vaddr = (vm_offset_t)contigmalloc_domain(PAGE_SIZE, 1159 M_DEVBUF, dmat->common.domain, M_NOWAIT, 0ul, 1160 bz->lowaddr, PAGE_SIZE, 0); 1161 if (bpage->vaddr == 0) { 1162 free_domain(bpage, M_DEVBUF); 1163 break; 1164 } 1165 bpage->busaddr = pmap_kextract(bpage->vaddr); 1166 mtx_lock(&bounce_lock); 1167 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1168 total_bpages++; 1169 bz->total_bpages++; 1170 bz->free_bpages++; 1171 mtx_unlock(&bounce_lock); 1172 count++; 1173 numpages--; 1174 } 1175 return (count); 1176 } 1177 1178 static int 1179 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1180 { 1181 struct bounce_zone *bz; 1182 int pages; 1183 1184 mtx_assert(&bounce_lock, MA_OWNED); 1185 bz = dmat->bounce_zone; 1186 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1187 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1188 return (map->pagesneeded - (map->pagesreserved + pages)); 1189 bz->free_bpages -= pages; 1190 bz->reserved_bpages += pages; 1191 map->pagesreserved += pages; 1192 pages = map->pagesneeded - map->pagesreserved; 1193 1194 return (pages); 1195 } 1196 1197 static bus_addr_t 1198 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1199 bus_addr_t addr1, bus_addr_t addr2, bus_size_t size) 1200 { 1201 struct bounce_zone *bz; 1202 struct bounce_page *bpage; 1203 1204 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1205 KASSERT(map != NULL && map != &nobounce_dmamap, 1206 ("add_bounce_page: bad map %p", map)); 1207 1208 bz = dmat->bounce_zone; 1209 if (map->pagesneeded == 0) 1210 panic("add_bounce_page: map doesn't need any pages"); 1211 map->pagesneeded--; 1212 1213 if (map->pagesreserved == 0) 1214 panic("add_bounce_page: map doesn't need any pages"); 1215 map->pagesreserved--; 1216 1217 mtx_lock(&bounce_lock); 1218 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1219 if (bpage == NULL) 1220 panic("add_bounce_page: free page list is empty"); 1221 1222 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1223 bz->reserved_bpages--; 1224 bz->active_bpages++; 1225 mtx_unlock(&bounce_lock); 1226 1227 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1228 /* Page offset needs to be preserved. */ 1229 bpage->vaddr |= addr1 & PAGE_MASK; 1230 bpage->busaddr |= addr1 & PAGE_MASK; 1231 KASSERT(addr2 == 0, 1232 ("Trying to bounce multiple pages with BUS_DMA_KEEP_PG_OFFSET")); 1233 } 1234 bpage->datavaddr = vaddr; 1235 bpage->datapage[0] = PHYS_TO_VM_PAGE(addr1); 1236 KASSERT((addr2 & PAGE_MASK) == 0, ("Second page is not aligned")); 1237 bpage->datapage[1] = PHYS_TO_VM_PAGE(addr2); 1238 bpage->dataoffs = addr1 & PAGE_MASK; 1239 bpage->datacount = size; 1240 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1241 return (bpage->busaddr); 1242 } 1243 1244 static void 1245 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1246 { 1247 struct bus_dmamap *map; 1248 struct bounce_zone *bz; 1249 1250 bz = dmat->bounce_zone; 1251 bpage->datavaddr = 0; 1252 bpage->datacount = 0; 1253 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1254 /* 1255 * Reset the bounce page to start at offset 0. Other uses 1256 * of this bounce page may need to store a full page of 1257 * data and/or assume it starts on a page boundary. 1258 */ 1259 bpage->vaddr &= ~PAGE_MASK; 1260 bpage->busaddr &= ~PAGE_MASK; 1261 } 1262 1263 mtx_lock(&bounce_lock); 1264 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1265 bz->free_bpages++; 1266 bz->active_bpages--; 1267 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1268 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1269 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1270 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1271 map, links); 1272 busdma_swi_pending = 1; 1273 bz->total_deferred++; 1274 swi_sched(vm_ih, 0); 1275 } 1276 } 1277 mtx_unlock(&bounce_lock); 1278 } 1279 1280 void 1281 busdma_swi(void) 1282 { 1283 bus_dma_tag_t dmat; 1284 struct bus_dmamap *map; 1285 1286 mtx_lock(&bounce_lock); 1287 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1288 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1289 mtx_unlock(&bounce_lock); 1290 dmat = map->dmat; 1291 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK); 1292 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1293 map->callback, map->callback_arg, BUS_DMA_WAITOK); 1294 (dmat->common.lockfunc)(dmat->common.lockfuncarg, 1295 BUS_DMA_UNLOCK); 1296 mtx_lock(&bounce_lock); 1297 } 1298 mtx_unlock(&bounce_lock); 1299 } 1300 1301 struct bus_dma_impl bus_dma_bounce_impl = { 1302 .tag_create = bounce_bus_dma_tag_create, 1303 .tag_destroy = bounce_bus_dma_tag_destroy, 1304 .tag_set_domain = bounce_bus_dma_tag_set_domain, 1305 .map_create = bounce_bus_dmamap_create, 1306 .map_destroy = bounce_bus_dmamap_destroy, 1307 .mem_alloc = bounce_bus_dmamem_alloc, 1308 .mem_free = bounce_bus_dmamem_free, 1309 .load_phys = bounce_bus_dmamap_load_phys, 1310 .load_buffer = bounce_bus_dmamap_load_buffer, 1311 .load_ma = bounce_bus_dmamap_load_ma, 1312 .map_waitok = bounce_bus_dmamap_waitok, 1313 .map_complete = bounce_bus_dmamap_complete, 1314 .map_unload = bounce_bus_dmamap_unload, 1315 .map_sync = bounce_bus_dmamap_sync, 1316 }; 1317