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/domainset.h> 35 #include <sys/malloc.h> 36 #include <sys/bus.h> 37 #include <sys/interrupt.h> 38 #include <sys/kernel.h> 39 #include <sys/ktr.h> 40 #include <sys/lock.h> 41 #include <sys/proc.h> 42 #include <sys/memdesc.h> 43 #include <sys/mutex.h> 44 #include <sys/sysctl.h> 45 #include <sys/uio.h> 46 47 #include <vm/vm.h> 48 #include <vm/vm_extern.h> 49 #include <vm/vm_kern.h> 50 #include <vm/vm_page.h> 51 #include <vm/vm_map.h> 52 53 #include <machine/atomic.h> 54 #include <machine/bus.h> 55 #include <machine/md_var.h> 56 #include <machine/specialreg.h> 57 #include <x86/include/busdma_impl.h> 58 59 #ifdef __i386__ 60 #define MAX_BPAGES (Maxmem > atop(0x100000000ULL) ? 8192 : 512) 61 #else 62 #define MAX_BPAGES 8192 63 #endif 64 65 enum { 66 BUS_DMA_COULD_BOUNCE = 0x01, 67 BUS_DMA_MIN_ALLOC_COMP = 0x02, 68 BUS_DMA_KMEM_ALLOC = 0x04, 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_offset_t dataoffs; /* page offset of client data */ 86 vm_page_t datapage[2]; /* physical page(s) 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 int domain; 104 bus_size_t alignment; 105 bus_addr_t lowaddr; 106 char zoneid[8]; 107 char lowaddrid[20]; 108 struct sysctl_ctx_list sysctl_tree; 109 struct sysctl_oid *sysctl_tree_top; 110 }; 111 112 static struct mtx bounce_lock; 113 static int total_bpages; 114 static int busdma_zonecount; 115 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 116 117 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 118 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 119 "Total bounce pages"); 120 121 struct bus_dmamap { 122 struct bp_list bpages; 123 int pagesneeded; 124 int pagesreserved; 125 bus_dma_tag_t dmat; 126 struct memdesc mem; 127 bus_dmamap_callback_t *callback; 128 void *callback_arg; 129 STAILQ_ENTRY(bus_dmamap) links; 130 }; 131 132 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 133 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 134 static struct bus_dmamap nobounce_dmamap; 135 136 static void init_bounce_pages(void *dummy); 137 static int alloc_bounce_zone(bus_dma_tag_t dmat); 138 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 139 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 140 int commit); 141 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 142 vm_offset_t vaddr, vm_paddr_t addr1, vm_paddr_t addr2, bus_size_t size); 143 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 144 static bool _bus_dmamap_pagesneeded(bus_dma_tag_t dmat, vm_paddr_t buf, 145 bus_size_t buflen, int *pagesneeded); 146 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 147 pmap_t pmap, void *buf, bus_size_t buflen, 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, int flags); 150 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 151 int flags); 152 153 static int 154 bounce_bus_dma_zone_setup(bus_dma_tag_t dmat) 155 { 156 struct bounce_zone *bz; 157 int error; 158 159 /* Must bounce */ 160 if ((error = alloc_bounce_zone(dmat)) != 0) 161 return (error); 162 bz = dmat->bounce_zone; 163 164 if (ptoa(bz->total_bpages) < dmat->common.maxsize) { 165 int pages; 166 167 pages = atop(dmat->common.maxsize) - bz->total_bpages; 168 169 /* Add pages to our bounce pool */ 170 if (alloc_bounce_pages(dmat, pages) < pages) 171 return (ENOMEM); 172 } 173 /* Performed initial allocation */ 174 dmat->bounce_flags |= BUS_DMA_MIN_ALLOC_COMP; 175 176 return (0); 177 } 178 179 /* 180 * Allocate a device specific dma_tag. 181 */ 182 static int 183 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 184 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr, 185 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize, 186 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 187 void *lockfuncarg, bus_dma_tag_t *dmat) 188 { 189 bus_dma_tag_t newtag; 190 int error; 191 192 *dmat = NULL; 193 error = common_bus_dma_tag_create(parent != NULL ? &parent->common : 194 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg, 195 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg, 196 sizeof (struct bus_dma_tag), (void **)&newtag); 197 if (error != 0) 198 return (error); 199 200 newtag->common.impl = &bus_dma_bounce_impl; 201 newtag->map_count = 0; 202 newtag->segments = NULL; 203 204 if (parent != NULL && (newtag->common.filter != NULL || 205 (parent->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0)) 206 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE; 207 208 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) || 209 newtag->common.alignment > 1) 210 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE; 211 212 if ((newtag->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 213 (flags & BUS_DMA_ALLOCNOW) != 0) 214 error = bounce_bus_dma_zone_setup(newtag); 215 else 216 error = 0; 217 218 if (error != 0) 219 free(newtag, M_DEVBUF); 220 else 221 *dmat = newtag; 222 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 223 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0), 224 error); 225 return (error); 226 } 227 228 static bool 229 bounce_bus_dma_id_mapped(bus_dma_tag_t dmat, vm_paddr_t buf, bus_size_t buflen) 230 { 231 232 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) == 0) 233 return (true); 234 return (!_bus_dmamap_pagesneeded(dmat, buf, buflen, NULL)); 235 } 236 237 /* 238 * Update the domain for the tag. We may need to reallocate the zone and 239 * bounce pages. 240 */ 241 static int 242 bounce_bus_dma_tag_set_domain(bus_dma_tag_t dmat) 243 { 244 245 KASSERT(dmat->map_count == 0, 246 ("bounce_bus_dma_tag_set_domain: Domain set after use.\n")); 247 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) == 0 || 248 dmat->bounce_zone == NULL) 249 return (0); 250 dmat->bounce_flags &= ~BUS_DMA_MIN_ALLOC_COMP; 251 return (bounce_bus_dma_zone_setup(dmat)); 252 } 253 254 static int 255 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat) 256 { 257 bus_dma_tag_t dmat_copy, parent; 258 int error; 259 260 error = 0; 261 dmat_copy = dmat; 262 263 if (dmat != NULL) { 264 if (dmat->map_count != 0) { 265 error = EBUSY; 266 goto out; 267 } 268 while (dmat != NULL) { 269 parent = (bus_dma_tag_t)dmat->common.parent; 270 atomic_subtract_int(&dmat->common.ref_count, 1); 271 if (dmat->common.ref_count == 0) { 272 if (dmat->segments != NULL) 273 free_domain(dmat->segments, M_DEVBUF); 274 free(dmat, M_DEVBUF); 275 /* 276 * Last reference count, so 277 * release our reference 278 * count on our parent. 279 */ 280 dmat = parent; 281 } else 282 dmat = NULL; 283 } 284 } 285 out: 286 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 287 return (error); 288 } 289 290 /* 291 * Allocate a handle for mapping from kva/uva/physical 292 * address space into bus device space. 293 */ 294 static int 295 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 296 { 297 struct bounce_zone *bz; 298 int error, maxpages, pages; 299 300 error = 0; 301 302 if (dmat->segments == NULL) { 303 dmat->segments = (bus_dma_segment_t *)malloc_domainset( 304 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 305 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), M_NOWAIT); 306 if (dmat->segments == NULL) { 307 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 308 __func__, dmat, ENOMEM); 309 return (ENOMEM); 310 } 311 } 312 313 /* 314 * Bouncing might be required if the driver asks for an active 315 * exclusion region, a data alignment that is stricter than 1, and/or 316 * an active address boundary. 317 */ 318 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 319 /* Must bounce */ 320 if (dmat->bounce_zone == NULL) { 321 if ((error = alloc_bounce_zone(dmat)) != 0) 322 return (error); 323 } 324 bz = dmat->bounce_zone; 325 326 *mapp = (bus_dmamap_t)malloc_domainset(sizeof(**mapp), M_DEVBUF, 327 DOMAINSET_PREF(dmat->common.domain), M_NOWAIT | M_ZERO); 328 if (*mapp == NULL) { 329 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 330 __func__, dmat, ENOMEM); 331 return (ENOMEM); 332 } 333 334 /* Initialize the new map */ 335 STAILQ_INIT(&((*mapp)->bpages)); 336 337 /* 338 * Attempt to add pages to our pool on a per-instance 339 * basis up to a sane limit. 340 */ 341 if (dmat->common.alignment > 1) 342 maxpages = MAX_BPAGES; 343 else 344 maxpages = MIN(MAX_BPAGES, Maxmem - 345 atop(dmat->common.lowaddr)); 346 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) == 0 || 347 (bz->map_count > 0 && bz->total_bpages < maxpages)) { 348 pages = MAX(atop(dmat->common.maxsize), 1); 349 pages = MIN(maxpages - bz->total_bpages, pages); 350 pages = MAX(pages, 1); 351 if (alloc_bounce_pages(dmat, pages) < pages) 352 error = ENOMEM; 353 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) 354 == 0) { 355 if (error == 0) { 356 dmat->bounce_flags |= 357 BUS_DMA_MIN_ALLOC_COMP; 358 } 359 } else 360 error = 0; 361 } 362 bz->map_count++; 363 } else { 364 *mapp = NULL; 365 } 366 if (error == 0) 367 dmat->map_count++; 368 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 369 __func__, dmat, dmat->common.flags, error); 370 return (error); 371 } 372 373 /* 374 * Destroy a handle for mapping from kva/uva/physical 375 * address space into bus device space. 376 */ 377 static int 378 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 379 { 380 381 if (map != NULL && map != &nobounce_dmamap) { 382 if (STAILQ_FIRST(&map->bpages) != NULL) { 383 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 384 __func__, dmat, EBUSY); 385 return (EBUSY); 386 } 387 if (dmat->bounce_zone) 388 dmat->bounce_zone->map_count--; 389 free_domain(map, M_DEVBUF); 390 } 391 dmat->map_count--; 392 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 393 return (0); 394 } 395 396 397 /* 398 * Allocate a piece of memory that can be efficiently mapped into 399 * bus device space based on the constraints lited in the dma tag. 400 * A dmamap to for use with dmamap_load is also allocated. 401 */ 402 static int 403 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 404 bus_dmamap_t *mapp) 405 { 406 vm_memattr_t attr; 407 int mflags; 408 409 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s", __func__); 410 411 if (flags & BUS_DMA_NOWAIT) 412 mflags = M_NOWAIT; 413 else 414 mflags = M_WAITOK; 415 416 /* If we succeed, no mapping/bouncing will be required */ 417 *mapp = NULL; 418 419 if (dmat->segments == NULL) { 420 dmat->segments = (bus_dma_segment_t *)malloc_domainset( 421 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 422 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), mflags); 423 if (dmat->segments == NULL) { 424 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 425 __func__, dmat, dmat->common.flags, ENOMEM); 426 return (ENOMEM); 427 } 428 } 429 if (flags & BUS_DMA_ZERO) 430 mflags |= M_ZERO; 431 if (flags & BUS_DMA_NOCACHE) 432 attr = VM_MEMATTR_UNCACHEABLE; 433 else 434 attr = VM_MEMATTR_DEFAULT; 435 436 /* 437 * Allocate the buffer from the malloc(9) allocator if... 438 * - It's small enough to fit into a single power of two sized bucket. 439 * - The alignment is less than or equal to the maximum size 440 * - The low address requirement is fulfilled. 441 * else allocate non-contiguous pages if... 442 * - The page count that could get allocated doesn't exceed 443 * nsegments also when the maximum segment size is less 444 * than PAGE_SIZE. 445 * - The alignment constraint isn't larger than a page boundary. 446 * - There are no boundary-crossing constraints. 447 * else allocate a block of contiguous pages because one or more of the 448 * constraints is something that only the contig allocator can fulfill. 449 * 450 * NOTE: The (dmat->common.alignment <= dmat->maxsize) check 451 * below is just a quick hack. The exact alignment guarantees 452 * of malloc(9) need to be nailed down, and the code below 453 * should be rewritten to take that into account. 454 * 455 * In the meantime warn the user if malloc gets it wrong. 456 */ 457 if (dmat->common.maxsize <= PAGE_SIZE && 458 dmat->common.alignment <= dmat->common.maxsize && 459 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) && 460 attr == VM_MEMATTR_DEFAULT) { 461 *vaddr = malloc_domainset(dmat->common.maxsize, M_DEVBUF, 462 DOMAINSET_PREF(dmat->common.domain), mflags); 463 } else if (dmat->common.nsegments >= 464 howmany(dmat->common.maxsize, MIN(dmat->common.maxsegsz, 465 PAGE_SIZE)) && 466 dmat->common.alignment <= PAGE_SIZE && 467 (dmat->common.boundary % PAGE_SIZE) == 0) { 468 /* Page-based multi-segment allocations allowed */ 469 *vaddr = (void *)kmem_alloc_attr_domainset( 470 DOMAINSET_PREF(dmat->common.domain), dmat->common.maxsize, 471 mflags, 0ul, dmat->common.lowaddr, attr); 472 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 473 } else { 474 *vaddr = (void *)kmem_alloc_contig_domainset( 475 DOMAINSET_PREF(dmat->common.domain), dmat->common.maxsize, 476 mflags, 0ul, dmat->common.lowaddr, 477 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul, 478 dmat->common.boundary, attr); 479 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 480 } 481 if (*vaddr == NULL) { 482 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 483 __func__, dmat, dmat->common.flags, ENOMEM); 484 return (ENOMEM); 485 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) { 486 printf("bus_dmamem_alloc failed to align memory properly.\n"); 487 } 488 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 489 __func__, dmat, dmat->common.flags, 0); 490 return (0); 491 } 492 493 /* 494 * Free a piece of memory and it's allociated dmamap, that was allocated 495 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 496 */ 497 static void 498 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 499 { 500 /* 501 * dmamem does not need to be bounced, so the map should be 502 * NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc() 503 * was used and set if kmem_alloc_contig() was used. 504 */ 505 if (map != NULL) 506 panic("bus_dmamem_free: Invalid map freed\n"); 507 if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0) 508 free_domain(vaddr, M_DEVBUF); 509 else 510 kmem_free((vm_offset_t)vaddr, dmat->common.maxsize); 511 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, 512 dmat->bounce_flags); 513 } 514 515 static bool 516 _bus_dmamap_pagesneeded(bus_dma_tag_t dmat, vm_paddr_t buf, bus_size_t buflen, 517 int *pagesneeded) 518 { 519 vm_paddr_t curaddr; 520 bus_size_t sgsize; 521 int count; 522 523 /* 524 * Count the number of bounce pages needed in order to 525 * complete this transfer 526 */ 527 count = 0; 528 curaddr = buf; 529 while (buflen != 0) { 530 sgsize = MIN(buflen, dmat->common.maxsegsz); 531 if (bus_dma_run_filter(&dmat->common, curaddr)) { 532 sgsize = MIN(sgsize, 533 PAGE_SIZE - (curaddr & PAGE_MASK)); 534 if (pagesneeded == NULL) 535 return (true); 536 count++; 537 } 538 curaddr += sgsize; 539 buflen -= sgsize; 540 } 541 542 if (pagesneeded != NULL) 543 *pagesneeded = count; 544 return (count != 0); 545 } 546 547 static void 548 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 549 bus_size_t buflen, int flags) 550 { 551 552 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 553 _bus_dmamap_pagesneeded(dmat, buf, buflen, &map->pagesneeded); 554 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 555 } 556 } 557 558 static void 559 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 560 void *buf, bus_size_t buflen, int flags) 561 { 562 vm_offset_t vaddr; 563 vm_offset_t vendaddr; 564 vm_paddr_t paddr; 565 bus_size_t sg_len; 566 567 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 568 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 569 "alignment= %d", dmat->common.lowaddr, 570 ptoa((vm_paddr_t)Maxmem), 571 dmat->common.boundary, dmat->common.alignment); 572 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 573 map, &nobounce_dmamap, map->pagesneeded); 574 /* 575 * Count the number of bounce pages 576 * needed in order to complete this transfer 577 */ 578 vaddr = (vm_offset_t)buf; 579 vendaddr = (vm_offset_t)buf + buflen; 580 581 while (vaddr < vendaddr) { 582 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 583 if (pmap == kernel_pmap) 584 paddr = pmap_kextract(vaddr); 585 else 586 paddr = pmap_extract(pmap, vaddr); 587 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 588 sg_len = roundup2(sg_len, 589 dmat->common.alignment); 590 map->pagesneeded++; 591 } 592 vaddr += sg_len; 593 } 594 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 595 } 596 } 597 598 static void 599 _bus_dmamap_count_ma(bus_dma_tag_t dmat, bus_dmamap_t map, struct vm_page **ma, 600 int ma_offs, bus_size_t buflen, int flags) 601 { 602 bus_size_t sg_len, max_sgsize; 603 int page_index; 604 vm_paddr_t paddr; 605 606 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 607 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 608 "alignment= %d", dmat->common.lowaddr, 609 ptoa((vm_paddr_t)Maxmem), 610 dmat->common.boundary, dmat->common.alignment); 611 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 612 map, &nobounce_dmamap, map->pagesneeded); 613 614 /* 615 * Count the number of bounce pages 616 * needed in order to complete this transfer 617 */ 618 page_index = 0; 619 while (buflen > 0) { 620 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 621 sg_len = PAGE_SIZE - ma_offs; 622 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 623 sg_len = MIN(sg_len, max_sgsize); 624 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 625 sg_len = roundup2(sg_len, 626 dmat->common.alignment); 627 sg_len = MIN(sg_len, max_sgsize); 628 KASSERT((sg_len & (dmat->common.alignment - 1)) 629 == 0, ("Segment size is not aligned")); 630 map->pagesneeded++; 631 } 632 if (((ma_offs + sg_len) & ~PAGE_MASK) != 0) 633 page_index++; 634 ma_offs = (ma_offs + sg_len) & PAGE_MASK; 635 KASSERT(buflen >= sg_len, 636 ("Segment length overruns original buffer")); 637 buflen -= sg_len; 638 } 639 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 640 } 641 } 642 643 static int 644 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 645 { 646 647 /* Reserve Necessary Bounce Pages */ 648 mtx_lock(&bounce_lock); 649 if (flags & BUS_DMA_NOWAIT) { 650 if (reserve_bounce_pages(dmat, map, 0) != 0) { 651 mtx_unlock(&bounce_lock); 652 return (ENOMEM); 653 } 654 } else { 655 if (reserve_bounce_pages(dmat, map, 1) != 0) { 656 /* Queue us for resources */ 657 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 658 mtx_unlock(&bounce_lock); 659 return (EINPROGRESS); 660 } 661 } 662 mtx_unlock(&bounce_lock); 663 664 return (0); 665 } 666 667 /* 668 * Add a single contiguous physical range to the segment list. 669 */ 670 static bus_size_t 671 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t curaddr, 672 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 673 { 674 bus_addr_t baddr, bmask; 675 int seg; 676 677 KASSERT(curaddr <= BUS_SPACE_MAXADDR, 678 ("ds_addr %#jx > BUS_SPACE_MAXADDR %#jx; dmat %p fl %#x low %#jx " 679 "hi %#jx", 680 (uintmax_t)curaddr, (uintmax_t)BUS_SPACE_MAXADDR, 681 dmat, dmat->bounce_flags, (uintmax_t)dmat->common.lowaddr, 682 (uintmax_t)dmat->common.highaddr)); 683 684 /* 685 * Make sure we don't cross any boundaries. 686 */ 687 bmask = ~(dmat->common.boundary - 1); 688 if (dmat->common.boundary > 0) { 689 baddr = (curaddr + dmat->common.boundary) & bmask; 690 if (sgsize > (baddr - curaddr)) 691 sgsize = (baddr - curaddr); 692 } 693 694 /* 695 * Insert chunk into a segment, coalescing with 696 * previous segment if possible. 697 */ 698 seg = *segp; 699 if (seg == -1) { 700 seg = 0; 701 segs[seg].ds_addr = curaddr; 702 segs[seg].ds_len = sgsize; 703 } else { 704 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 705 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz && 706 (dmat->common.boundary == 0 || 707 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 708 segs[seg].ds_len += sgsize; 709 else { 710 if (++seg >= dmat->common.nsegments) 711 return (0); 712 segs[seg].ds_addr = curaddr; 713 segs[seg].ds_len = sgsize; 714 } 715 } 716 *segp = seg; 717 return (sgsize); 718 } 719 720 /* 721 * Utility function to load a physical buffer. segp contains 722 * the starting segment on entrace, and the ending segment on exit. 723 */ 724 static int 725 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 726 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, 727 int *segp) 728 { 729 bus_size_t sgsize; 730 vm_paddr_t curaddr; 731 int error; 732 733 if (map == NULL) 734 map = &nobounce_dmamap; 735 736 if (segs == NULL) 737 segs = dmat->segments; 738 739 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 740 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 741 if (map->pagesneeded != 0) { 742 error = _bus_dmamap_reserve_pages(dmat, map, flags); 743 if (error) 744 return (error); 745 } 746 } 747 748 while (buflen > 0) { 749 curaddr = buf; 750 sgsize = MIN(buflen, dmat->common.maxsegsz); 751 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 752 map->pagesneeded != 0 && 753 bus_dma_run_filter(&dmat->common, curaddr)) { 754 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK)); 755 curaddr = add_bounce_page(dmat, map, 0, curaddr, 0, 756 sgsize); 757 } 758 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 759 segp); 760 if (sgsize == 0) 761 break; 762 buf += sgsize; 763 buflen -= sgsize; 764 } 765 766 /* 767 * Did we fit? 768 */ 769 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 770 } 771 772 /* 773 * Utility function to load a linear buffer. segp contains 774 * the starting segment on entrace, and the ending segment on exit. 775 */ 776 static int 777 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 778 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, 779 int *segp) 780 { 781 bus_size_t sgsize, max_sgsize; 782 vm_paddr_t curaddr; 783 vm_offset_t kvaddr, vaddr; 784 int error; 785 786 if (map == NULL) 787 map = &nobounce_dmamap; 788 789 if (segs == NULL) 790 segs = dmat->segments; 791 792 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 793 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 794 if (map->pagesneeded != 0) { 795 error = _bus_dmamap_reserve_pages(dmat, map, flags); 796 if (error) 797 return (error); 798 } 799 } 800 801 vaddr = (vm_offset_t)buf; 802 while (buflen > 0) { 803 /* 804 * Get the physical address for this segment. 805 */ 806 if (pmap == kernel_pmap) { 807 curaddr = pmap_kextract(vaddr); 808 kvaddr = vaddr; 809 } else { 810 curaddr = pmap_extract(pmap, vaddr); 811 kvaddr = 0; 812 } 813 814 /* 815 * Compute the segment size, and adjust counts. 816 */ 817 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 818 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK); 819 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 820 map->pagesneeded != 0 && 821 bus_dma_run_filter(&dmat->common, curaddr)) { 822 sgsize = roundup2(sgsize, dmat->common.alignment); 823 sgsize = MIN(sgsize, max_sgsize); 824 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr, 0, 825 sgsize); 826 } else { 827 sgsize = MIN(sgsize, max_sgsize); 828 } 829 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 830 segp); 831 if (sgsize == 0) 832 break; 833 vaddr += sgsize; 834 buflen -= sgsize; 835 } 836 837 /* 838 * Did we fit? 839 */ 840 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 841 } 842 843 static int 844 bounce_bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map, 845 struct vm_page **ma, bus_size_t buflen, int ma_offs, int flags, 846 bus_dma_segment_t *segs, int *segp) 847 { 848 vm_paddr_t paddr, next_paddr; 849 int error, page_index; 850 bus_size_t sgsize, max_sgsize; 851 852 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 853 /* 854 * If we have to keep the offset of each page this function 855 * is not suitable, switch back to bus_dmamap_load_ma_triv 856 * which is going to do the right thing in this case. 857 */ 858 error = bus_dmamap_load_ma_triv(dmat, map, ma, buflen, ma_offs, 859 flags, segs, segp); 860 return (error); 861 } 862 863 if (map == NULL) 864 map = &nobounce_dmamap; 865 866 if (segs == NULL) 867 segs = dmat->segments; 868 869 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 870 _bus_dmamap_count_ma(dmat, map, ma, ma_offs, buflen, flags); 871 if (map->pagesneeded != 0) { 872 error = _bus_dmamap_reserve_pages(dmat, map, flags); 873 if (error) 874 return (error); 875 } 876 } 877 878 page_index = 0; 879 while (buflen > 0) { 880 /* 881 * Compute the segment size, and adjust counts. 882 */ 883 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 884 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 885 sgsize = PAGE_SIZE - ma_offs; 886 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 887 map->pagesneeded != 0 && 888 bus_dma_run_filter(&dmat->common, paddr)) { 889 sgsize = roundup2(sgsize, dmat->common.alignment); 890 sgsize = MIN(sgsize, max_sgsize); 891 KASSERT((sgsize & (dmat->common.alignment - 1)) == 0, 892 ("Segment size is not aligned")); 893 /* 894 * Check if two pages of the user provided buffer 895 * are used. 896 */ 897 if ((ma_offs + sgsize) > PAGE_SIZE) 898 next_paddr = 899 VM_PAGE_TO_PHYS(ma[page_index + 1]); 900 else 901 next_paddr = 0; 902 paddr = add_bounce_page(dmat, map, 0, paddr, 903 next_paddr, sgsize); 904 } else { 905 sgsize = MIN(sgsize, max_sgsize); 906 } 907 sgsize = _bus_dmamap_addseg(dmat, map, paddr, sgsize, segs, 908 segp); 909 if (sgsize == 0) 910 break; 911 KASSERT(buflen >= sgsize, 912 ("Segment length overruns original buffer")); 913 buflen -= sgsize; 914 if (((ma_offs + sgsize) & ~PAGE_MASK) != 0) 915 page_index++; 916 ma_offs = (ma_offs + sgsize) & PAGE_MASK; 917 } 918 919 /* 920 * Did we fit? 921 */ 922 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 923 } 924 925 static void 926 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 927 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) 928 { 929 930 if (map == NULL) 931 return; 932 map->mem = *mem; 933 map->dmat = dmat; 934 map->callback = callback; 935 map->callback_arg = callback_arg; 936 } 937 938 static bus_dma_segment_t * 939 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 940 bus_dma_segment_t *segs, int nsegs, int error) 941 { 942 943 if (segs == NULL) 944 segs = dmat->segments; 945 return (segs); 946 } 947 948 /* 949 * Release the mapping held by map. 950 */ 951 static void 952 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 953 { 954 struct bounce_page *bpage; 955 956 if (map == NULL) 957 return; 958 959 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 960 STAILQ_REMOVE_HEAD(&map->bpages, links); 961 free_bounce_page(dmat, bpage); 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 vm_offset_t datavaddr, tempvaddr; 971 bus_size_t datacount1, datacount2; 972 973 if (map == NULL || (bpage = STAILQ_FIRST(&map->bpages)) == NULL) 974 return; 975 976 /* 977 * Handle data bouncing. We might also want to add support for 978 * invalidating the caches on broken hardware. 979 */ 980 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 981 "performing bounce", __func__, dmat, dmat->common.flags, op); 982 983 if ((op & BUS_DMASYNC_PREWRITE) != 0) { 984 while (bpage != NULL) { 985 tempvaddr = 0; 986 datavaddr = bpage->datavaddr; 987 datacount1 = bpage->datacount; 988 if (datavaddr == 0) { 989 tempvaddr = 990 pmap_quick_enter_page(bpage->datapage[0]); 991 datavaddr = tempvaddr | bpage->dataoffs; 992 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 993 datacount1); 994 } 995 996 bcopy((void *)datavaddr, 997 (void *)bpage->vaddr, datacount1); 998 999 if (tempvaddr != 0) 1000 pmap_quick_remove_page(tempvaddr); 1001 1002 if (bpage->datapage[1] == 0) { 1003 KASSERT(datacount1 == bpage->datacount, 1004 ("Mismatch between data size and provided memory space")); 1005 goto next_w; 1006 } 1007 1008 /* 1009 * We are dealing with an unmapped buffer that expands 1010 * over two pages. 1011 */ 1012 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 1013 datacount2 = bpage->datacount - datacount1; 1014 bcopy((void *)datavaddr, 1015 (void *)(bpage->vaddr + datacount1), datacount2); 1016 pmap_quick_remove_page(datavaddr); 1017 1018 next_w: 1019 bpage = STAILQ_NEXT(bpage, links); 1020 } 1021 dmat->bounce_zone->total_bounced++; 1022 } 1023 1024 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 1025 while (bpage != NULL) { 1026 tempvaddr = 0; 1027 datavaddr = bpage->datavaddr; 1028 datacount1 = bpage->datacount; 1029 if (datavaddr == 0) { 1030 tempvaddr = 1031 pmap_quick_enter_page(bpage->datapage[0]); 1032 datavaddr = tempvaddr | bpage->dataoffs; 1033 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 1034 datacount1); 1035 } 1036 1037 bcopy((void *)bpage->vaddr, (void *)datavaddr, 1038 datacount1); 1039 1040 if (tempvaddr != 0) 1041 pmap_quick_remove_page(tempvaddr); 1042 1043 if (bpage->datapage[1] == 0) { 1044 KASSERT(datacount1 == bpage->datacount, 1045 ("Mismatch between data size and provided memory space")); 1046 goto next_r; 1047 } 1048 1049 /* 1050 * We are dealing with an unmapped buffer that expands 1051 * over two pages. 1052 */ 1053 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 1054 datacount2 = bpage->datacount - datacount1; 1055 bcopy((void *)(bpage->vaddr + datacount1), 1056 (void *)datavaddr, datacount2); 1057 pmap_quick_remove_page(datavaddr); 1058 1059 next_r: 1060 bpage = STAILQ_NEXT(bpage, links); 1061 } 1062 dmat->bounce_zone->total_bounced++; 1063 } 1064 } 1065 1066 static void 1067 init_bounce_pages(void *dummy __unused) 1068 { 1069 1070 total_bpages = 0; 1071 STAILQ_INIT(&bounce_zone_list); 1072 STAILQ_INIT(&bounce_map_waitinglist); 1073 STAILQ_INIT(&bounce_map_callbacklist); 1074 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 1075 } 1076 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 1077 1078 static struct sysctl_ctx_list * 1079 busdma_sysctl_tree(struct bounce_zone *bz) 1080 { 1081 1082 return (&bz->sysctl_tree); 1083 } 1084 1085 static struct sysctl_oid * 1086 busdma_sysctl_tree_top(struct bounce_zone *bz) 1087 { 1088 1089 return (bz->sysctl_tree_top); 1090 } 1091 1092 static int 1093 alloc_bounce_zone(bus_dma_tag_t dmat) 1094 { 1095 struct bounce_zone *bz; 1096 1097 /* Check to see if we already have a suitable zone */ 1098 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1099 if (dmat->common.alignment <= bz->alignment && 1100 dmat->common.lowaddr >= bz->lowaddr && 1101 dmat->common.domain == bz->domain) { 1102 dmat->bounce_zone = bz; 1103 return (0); 1104 } 1105 } 1106 1107 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1108 M_NOWAIT | M_ZERO)) == NULL) 1109 return (ENOMEM); 1110 1111 STAILQ_INIT(&bz->bounce_page_list); 1112 bz->free_bpages = 0; 1113 bz->reserved_bpages = 0; 1114 bz->active_bpages = 0; 1115 bz->lowaddr = dmat->common.lowaddr; 1116 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE); 1117 bz->map_count = 0; 1118 bz->domain = dmat->common.domain; 1119 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1120 busdma_zonecount++; 1121 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1122 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1123 dmat->bounce_zone = bz; 1124 1125 sysctl_ctx_init(&bz->sysctl_tree); 1126 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1127 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1128 CTLFLAG_RD, 0, ""); 1129 if (bz->sysctl_tree_top == NULL) { 1130 sysctl_ctx_free(&bz->sysctl_tree); 1131 return (0); /* XXX error code? */ 1132 } 1133 1134 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1135 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1136 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1137 "Total bounce pages"); 1138 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1139 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1140 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1141 "Free bounce pages"); 1142 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1143 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1144 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1145 "Reserved bounce pages"); 1146 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1147 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1148 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1149 "Active bounce pages"); 1150 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1151 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1152 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1153 "Total bounce requests"); 1154 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1155 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1156 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1157 "Total bounce requests that were deferred"); 1158 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1159 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1160 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1161 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz), 1162 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1163 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1164 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1165 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1166 "domain", CTLFLAG_RD, &bz->domain, 0, 1167 "memory domain"); 1168 1169 return (0); 1170 } 1171 1172 static int 1173 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1174 { 1175 struct bounce_zone *bz; 1176 int count; 1177 1178 bz = dmat->bounce_zone; 1179 count = 0; 1180 while (numpages > 0) { 1181 struct bounce_page *bpage; 1182 1183 bpage = malloc_domainset(sizeof(*bpage), M_DEVBUF, 1184 DOMAINSET_PREF(dmat->common.domain), M_NOWAIT | M_ZERO); 1185 1186 if (bpage == NULL) 1187 break; 1188 bpage->vaddr = (vm_offset_t)contigmalloc_domainset(PAGE_SIZE, 1189 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), M_NOWAIT, 1190 0ul, bz->lowaddr, PAGE_SIZE, 0); 1191 if (bpage->vaddr == 0) { 1192 free_domain(bpage, M_DEVBUF); 1193 break; 1194 } 1195 bpage->busaddr = pmap_kextract(bpage->vaddr); 1196 mtx_lock(&bounce_lock); 1197 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1198 total_bpages++; 1199 bz->total_bpages++; 1200 bz->free_bpages++; 1201 mtx_unlock(&bounce_lock); 1202 count++; 1203 numpages--; 1204 } 1205 return (count); 1206 } 1207 1208 static int 1209 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1210 { 1211 struct bounce_zone *bz; 1212 int pages; 1213 1214 mtx_assert(&bounce_lock, MA_OWNED); 1215 bz = dmat->bounce_zone; 1216 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1217 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1218 return (map->pagesneeded - (map->pagesreserved + pages)); 1219 bz->free_bpages -= pages; 1220 bz->reserved_bpages += pages; 1221 map->pagesreserved += pages; 1222 pages = map->pagesneeded - map->pagesreserved; 1223 1224 return (pages); 1225 } 1226 1227 static bus_addr_t 1228 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1229 vm_paddr_t addr1, vm_paddr_t addr2, bus_size_t size) 1230 { 1231 struct bounce_zone *bz; 1232 struct bounce_page *bpage; 1233 1234 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1235 KASSERT(map != NULL && map != &nobounce_dmamap, 1236 ("add_bounce_page: bad map %p", map)); 1237 1238 bz = dmat->bounce_zone; 1239 if (map->pagesneeded == 0) 1240 panic("add_bounce_page: map doesn't need any pages"); 1241 map->pagesneeded--; 1242 1243 if (map->pagesreserved == 0) 1244 panic("add_bounce_page: map doesn't need any pages"); 1245 map->pagesreserved--; 1246 1247 mtx_lock(&bounce_lock); 1248 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1249 if (bpage == NULL) 1250 panic("add_bounce_page: free page list is empty"); 1251 1252 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1253 bz->reserved_bpages--; 1254 bz->active_bpages++; 1255 mtx_unlock(&bounce_lock); 1256 1257 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1258 /* Page offset needs to be preserved. */ 1259 bpage->vaddr |= addr1 & PAGE_MASK; 1260 bpage->busaddr |= addr1 & PAGE_MASK; 1261 KASSERT(addr2 == 0, 1262 ("Trying to bounce multiple pages with BUS_DMA_KEEP_PG_OFFSET")); 1263 } 1264 bpage->datavaddr = vaddr; 1265 bpage->datapage[0] = PHYS_TO_VM_PAGE(addr1); 1266 KASSERT((addr2 & PAGE_MASK) == 0, ("Second page is not aligned")); 1267 bpage->datapage[1] = PHYS_TO_VM_PAGE(addr2); 1268 bpage->dataoffs = addr1 & PAGE_MASK; 1269 bpage->datacount = size; 1270 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1271 return (bpage->busaddr); 1272 } 1273 1274 static void 1275 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1276 { 1277 struct bus_dmamap *map; 1278 struct bounce_zone *bz; 1279 1280 bz = dmat->bounce_zone; 1281 bpage->datavaddr = 0; 1282 bpage->datacount = 0; 1283 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1284 /* 1285 * Reset the bounce page to start at offset 0. Other uses 1286 * of this bounce page may need to store a full page of 1287 * data and/or assume it starts on a page boundary. 1288 */ 1289 bpage->vaddr &= ~PAGE_MASK; 1290 bpage->busaddr &= ~PAGE_MASK; 1291 } 1292 1293 mtx_lock(&bounce_lock); 1294 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1295 bz->free_bpages++; 1296 bz->active_bpages--; 1297 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1298 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1299 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1300 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1301 map, links); 1302 busdma_swi_pending = 1; 1303 bz->total_deferred++; 1304 swi_sched(vm_ih, 0); 1305 } 1306 } 1307 mtx_unlock(&bounce_lock); 1308 } 1309 1310 void 1311 busdma_swi(void) 1312 { 1313 bus_dma_tag_t dmat; 1314 struct bus_dmamap *map; 1315 1316 mtx_lock(&bounce_lock); 1317 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1318 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1319 mtx_unlock(&bounce_lock); 1320 dmat = map->dmat; 1321 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK); 1322 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1323 map->callback, map->callback_arg, BUS_DMA_WAITOK); 1324 (dmat->common.lockfunc)(dmat->common.lockfuncarg, 1325 BUS_DMA_UNLOCK); 1326 mtx_lock(&bounce_lock); 1327 } 1328 mtx_unlock(&bounce_lock); 1329 } 1330 1331 struct bus_dma_impl bus_dma_bounce_impl = { 1332 .tag_create = bounce_bus_dma_tag_create, 1333 .tag_destroy = bounce_bus_dma_tag_destroy, 1334 .tag_set_domain = bounce_bus_dma_tag_set_domain, 1335 .id_mapped = bounce_bus_dma_id_mapped, 1336 .map_create = bounce_bus_dmamap_create, 1337 .map_destroy = bounce_bus_dmamap_destroy, 1338 .mem_alloc = bounce_bus_dmamem_alloc, 1339 .mem_free = bounce_bus_dmamem_free, 1340 .load_phys = bounce_bus_dmamap_load_phys, 1341 .load_buffer = bounce_bus_dmamap_load_buffer, 1342 .load_ma = bounce_bus_dmamap_load_ma, 1343 .map_waitok = bounce_bus_dmamap_waitok, 1344 .map_complete = bounce_bus_dmamap_complete, 1345 .map_unload = bounce_bus_dmamap_unload, 1346 .map_sync = bounce_bus_dmamap_sync, 1347 }; 1348