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 void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 145 pmap_t pmap, void *buf, bus_size_t buflen, int flags); 146 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 147 vm_paddr_t buf, bus_size_t buflen, int flags); 148 static int _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 149 int flags); 150 151 static int 152 bounce_bus_dma_zone_setup(bus_dma_tag_t dmat) 153 { 154 struct bounce_zone *bz; 155 int error; 156 157 /* Must bounce */ 158 if ((error = alloc_bounce_zone(dmat)) != 0) 159 return (error); 160 bz = dmat->bounce_zone; 161 162 if (ptoa(bz->total_bpages) < dmat->common.maxsize) { 163 int pages; 164 165 pages = atop(dmat->common.maxsize) - bz->total_bpages; 166 167 /* Add pages to our bounce pool */ 168 if (alloc_bounce_pages(dmat, pages) < pages) 169 return (ENOMEM); 170 } 171 /* Performed initial allocation */ 172 dmat->bounce_flags |= BUS_DMA_MIN_ALLOC_COMP; 173 174 return (0); 175 } 176 177 /* 178 * Allocate a device specific dma_tag. 179 */ 180 static int 181 bounce_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 182 bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr, 183 bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize, 184 int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 185 void *lockfuncarg, bus_dma_tag_t *dmat) 186 { 187 bus_dma_tag_t newtag; 188 int error; 189 190 *dmat = NULL; 191 error = common_bus_dma_tag_create(parent != NULL ? &parent->common : 192 NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg, 193 maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg, 194 sizeof (struct bus_dma_tag), (void **)&newtag); 195 if (error != 0) 196 return (error); 197 198 newtag->common.impl = &bus_dma_bounce_impl; 199 newtag->map_count = 0; 200 newtag->segments = NULL; 201 202 if (parent != NULL && (newtag->common.filter != NULL || 203 (parent->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0)) 204 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE; 205 206 if (newtag->common.lowaddr < ptoa((vm_paddr_t)Maxmem) || 207 newtag->common.alignment > 1) 208 newtag->bounce_flags |= BUS_DMA_COULD_BOUNCE; 209 210 if ((newtag->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 211 (flags & BUS_DMA_ALLOCNOW) != 0) 212 error = bounce_bus_dma_zone_setup(newtag); 213 else 214 error = 0; 215 216 if (error != 0) 217 free(newtag, M_DEVBUF); 218 else 219 *dmat = newtag; 220 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 221 __func__, newtag, (newtag != NULL ? newtag->common.flags : 0), 222 error); 223 return (error); 224 } 225 226 /* 227 * Update the domain for the tag. We may need to reallocate the zone and 228 * bounce pages. 229 */ 230 static int 231 bounce_bus_dma_tag_set_domain(bus_dma_tag_t dmat) 232 { 233 234 KASSERT(dmat->map_count == 0, 235 ("bounce_bus_dma_tag_set_domain: Domain set after use.\n")); 236 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) == 0 || 237 dmat->bounce_zone == NULL) 238 return (0); 239 dmat->bounce_flags &= ~BUS_DMA_MIN_ALLOC_COMP; 240 return (bounce_bus_dma_zone_setup(dmat)); 241 } 242 243 static int 244 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat) 245 { 246 bus_dma_tag_t dmat_copy, parent; 247 int error; 248 249 error = 0; 250 dmat_copy = dmat; 251 252 if (dmat != NULL) { 253 if (dmat->map_count != 0) { 254 error = EBUSY; 255 goto out; 256 } 257 while (dmat != NULL) { 258 parent = (bus_dma_tag_t)dmat->common.parent; 259 atomic_subtract_int(&dmat->common.ref_count, 1); 260 if (dmat->common.ref_count == 0) { 261 if (dmat->segments != NULL) 262 free_domain(dmat->segments, M_DEVBUF); 263 free(dmat, M_DEVBUF); 264 /* 265 * Last reference count, so 266 * release our reference 267 * count on our parent. 268 */ 269 dmat = parent; 270 } else 271 dmat = NULL; 272 } 273 } 274 out: 275 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 276 return (error); 277 } 278 279 /* 280 * Allocate a handle for mapping from kva/uva/physical 281 * address space into bus device space. 282 */ 283 static int 284 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 285 { 286 struct bounce_zone *bz; 287 int error, maxpages, pages; 288 289 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s", __func__); 290 291 error = 0; 292 293 if (dmat->segments == NULL) { 294 dmat->segments = (bus_dma_segment_t *)malloc_domainset( 295 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 296 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), M_NOWAIT); 297 if (dmat->segments == NULL) { 298 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 299 __func__, dmat, ENOMEM); 300 return (ENOMEM); 301 } 302 } 303 304 /* 305 * Bouncing might be required if the driver asks for an active 306 * exclusion region, a data alignment that is stricter than 1, and/or 307 * an active address boundary. 308 */ 309 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 310 /* Must bounce */ 311 if (dmat->bounce_zone == NULL) { 312 if ((error = alloc_bounce_zone(dmat)) != 0) 313 return (error); 314 } 315 bz = dmat->bounce_zone; 316 317 *mapp = (bus_dmamap_t)malloc_domainset(sizeof(**mapp), M_DEVBUF, 318 DOMAINSET_PREF(dmat->common.domain), M_NOWAIT | M_ZERO); 319 if (*mapp == NULL) { 320 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 321 __func__, dmat, ENOMEM); 322 return (ENOMEM); 323 } 324 325 /* Initialize the new map */ 326 STAILQ_INIT(&((*mapp)->bpages)); 327 328 /* 329 * Attempt to add pages to our pool on a per-instance 330 * basis up to a sane limit. 331 */ 332 if (dmat->common.alignment > 1) 333 maxpages = MAX_BPAGES; 334 else 335 maxpages = MIN(MAX_BPAGES, Maxmem - 336 atop(dmat->common.lowaddr)); 337 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) == 0 || 338 (bz->map_count > 0 && bz->total_bpages < maxpages)) { 339 pages = MAX(atop(dmat->common.maxsize), 1); 340 pages = MIN(maxpages - bz->total_bpages, pages); 341 pages = MAX(pages, 1); 342 if (alloc_bounce_pages(dmat, pages) < pages) 343 error = ENOMEM; 344 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) 345 == 0) { 346 if (error == 0) { 347 dmat->bounce_flags |= 348 BUS_DMA_MIN_ALLOC_COMP; 349 } 350 } else 351 error = 0; 352 } 353 bz->map_count++; 354 } else { 355 *mapp = NULL; 356 } 357 if (error == 0) 358 dmat->map_count++; 359 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 360 __func__, dmat, dmat->common.flags, error); 361 return (error); 362 } 363 364 /* 365 * Destroy a handle for mapping from kva/uva/physical 366 * address space into bus device space. 367 */ 368 static int 369 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 370 { 371 372 if (map != NULL && map != &nobounce_dmamap) { 373 if (STAILQ_FIRST(&map->bpages) != NULL) { 374 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 375 __func__, dmat, EBUSY); 376 return (EBUSY); 377 } 378 if (dmat->bounce_zone) 379 dmat->bounce_zone->map_count--; 380 free_domain(map, M_DEVBUF); 381 } 382 dmat->map_count--; 383 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 384 return (0); 385 } 386 387 388 /* 389 * Allocate a piece of memory that can be efficiently mapped into 390 * bus device space based on the constraints lited in the dma tag. 391 * A dmamap to for use with dmamap_load is also allocated. 392 */ 393 static int 394 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 395 bus_dmamap_t *mapp) 396 { 397 vm_memattr_t attr; 398 int mflags; 399 400 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "%s", __func__); 401 402 if (flags & BUS_DMA_NOWAIT) 403 mflags = M_NOWAIT; 404 else 405 mflags = M_WAITOK; 406 407 /* If we succeed, no mapping/bouncing will be required */ 408 *mapp = NULL; 409 410 if (dmat->segments == NULL) { 411 dmat->segments = (bus_dma_segment_t *)malloc_domainset( 412 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 413 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), mflags); 414 if (dmat->segments == NULL) { 415 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 416 __func__, dmat, dmat->common.flags, ENOMEM); 417 return (ENOMEM); 418 } 419 } 420 if (flags & BUS_DMA_ZERO) 421 mflags |= M_ZERO; 422 if (flags & BUS_DMA_NOCACHE) 423 attr = VM_MEMATTR_UNCACHEABLE; 424 else 425 attr = VM_MEMATTR_DEFAULT; 426 427 /* 428 * Allocate the buffer from the malloc(9) allocator if... 429 * - It's small enough to fit into a single power of two sized bucket. 430 * - The alignment is less than or equal to the maximum size 431 * - The low address requirement is fulfilled. 432 * else allocate non-contiguous pages if... 433 * - The page count that could get allocated doesn't exceed 434 * nsegments also when the maximum segment size is less 435 * than PAGE_SIZE. 436 * - The alignment constraint isn't larger than a page boundary. 437 * - There are no boundary-crossing constraints. 438 * else allocate a block of contiguous pages because one or more of the 439 * constraints is something that only the contig allocator can fulfill. 440 * 441 * NOTE: The (dmat->common.alignment <= dmat->maxsize) check 442 * below is just a quick hack. The exact alignment guarantees 443 * of malloc(9) need to be nailed down, and the code below 444 * should be rewritten to take that into account. 445 * 446 * In the meantime warn the user if malloc gets it wrong. 447 */ 448 if (dmat->common.maxsize <= PAGE_SIZE && 449 dmat->common.alignment <= dmat->common.maxsize && 450 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) && 451 attr == VM_MEMATTR_DEFAULT) { 452 *vaddr = malloc_domainset(dmat->common.maxsize, M_DEVBUF, 453 DOMAINSET_PREF(dmat->common.domain), mflags); 454 } else if (dmat->common.nsegments >= 455 howmany(dmat->common.maxsize, MIN(dmat->common.maxsegsz, 456 PAGE_SIZE)) && 457 dmat->common.alignment <= PAGE_SIZE && 458 (dmat->common.boundary % PAGE_SIZE) == 0) { 459 /* Page-based multi-segment allocations allowed */ 460 *vaddr = (void *)kmem_alloc_attr_domainset( 461 DOMAINSET_PREF(dmat->common.domain), dmat->common.maxsize, 462 mflags, 0ul, dmat->common.lowaddr, attr); 463 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 464 } else { 465 *vaddr = (void *)kmem_alloc_contig_domainset( 466 DOMAINSET_PREF(dmat->common.domain), dmat->common.maxsize, 467 mflags, 0ul, dmat->common.lowaddr, 468 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul, 469 dmat->common.boundary, attr); 470 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 471 } 472 if (*vaddr == NULL) { 473 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 474 __func__, dmat, dmat->common.flags, ENOMEM); 475 return (ENOMEM); 476 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) { 477 printf("bus_dmamem_alloc failed to align memory properly.\n"); 478 } 479 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 480 __func__, dmat, dmat->common.flags, 0); 481 return (0); 482 } 483 484 /* 485 * Free a piece of memory and it's allociated dmamap, that was allocated 486 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 487 */ 488 static void 489 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 490 { 491 /* 492 * dmamem does not need to be bounced, so the map should be 493 * NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc() 494 * was used and set if kmem_alloc_contig() was used. 495 */ 496 if (map != NULL) 497 panic("bus_dmamem_free: Invalid map freed\n"); 498 if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0) 499 free_domain(vaddr, M_DEVBUF); 500 else 501 kmem_free((vm_offset_t)vaddr, dmat->common.maxsize); 502 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, 503 dmat->bounce_flags); 504 } 505 506 static void 507 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 508 bus_size_t buflen, int flags) 509 { 510 vm_paddr_t curaddr; 511 bus_size_t sgsize; 512 513 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 514 /* 515 * Count the number of bounce pages 516 * needed in order to complete this transfer 517 */ 518 curaddr = buf; 519 while (buflen != 0) { 520 sgsize = MIN(buflen, dmat->common.maxsegsz); 521 if (bus_dma_run_filter(&dmat->common, curaddr)) { 522 sgsize = MIN(sgsize, 523 PAGE_SIZE - (curaddr & PAGE_MASK)); 524 map->pagesneeded++; 525 } 526 curaddr += sgsize; 527 buflen -= sgsize; 528 } 529 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 530 } 531 } 532 533 static void 534 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 535 void *buf, bus_size_t buflen, int flags) 536 { 537 vm_offset_t vaddr; 538 vm_offset_t vendaddr; 539 vm_paddr_t paddr; 540 bus_size_t sg_len; 541 542 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 543 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 544 "alignment= %d", dmat->common.lowaddr, 545 ptoa((vm_paddr_t)Maxmem), 546 dmat->common.boundary, dmat->common.alignment); 547 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 548 map, &nobounce_dmamap, map->pagesneeded); 549 /* 550 * Count the number of bounce pages 551 * needed in order to complete this transfer 552 */ 553 vaddr = (vm_offset_t)buf; 554 vendaddr = (vm_offset_t)buf + buflen; 555 556 while (vaddr < vendaddr) { 557 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 558 if (pmap == kernel_pmap) 559 paddr = pmap_kextract(vaddr); 560 else 561 paddr = pmap_extract(pmap, vaddr); 562 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 563 sg_len = roundup2(sg_len, 564 dmat->common.alignment); 565 map->pagesneeded++; 566 } 567 vaddr += sg_len; 568 } 569 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 570 } 571 } 572 573 static void 574 _bus_dmamap_count_ma(bus_dma_tag_t dmat, bus_dmamap_t map, struct vm_page **ma, 575 int ma_offs, bus_size_t buflen, int flags) 576 { 577 bus_size_t sg_len, max_sgsize; 578 int page_index; 579 vm_paddr_t paddr; 580 581 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 582 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 583 "alignment= %d", dmat->common.lowaddr, 584 ptoa((vm_paddr_t)Maxmem), 585 dmat->common.boundary, dmat->common.alignment); 586 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 587 map, &nobounce_dmamap, map->pagesneeded); 588 589 /* 590 * Count the number of bounce pages 591 * needed in order to complete this transfer 592 */ 593 page_index = 0; 594 while (buflen > 0) { 595 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 596 sg_len = PAGE_SIZE - ma_offs; 597 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 598 sg_len = MIN(sg_len, max_sgsize); 599 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 600 sg_len = roundup2(sg_len, 601 dmat->common.alignment); 602 sg_len = MIN(sg_len, max_sgsize); 603 KASSERT((sg_len & (dmat->common.alignment - 1)) 604 == 0, ("Segment size is not aligned")); 605 map->pagesneeded++; 606 } 607 if (((ma_offs + sg_len) & ~PAGE_MASK) != 0) 608 page_index++; 609 ma_offs = (ma_offs + sg_len) & PAGE_MASK; 610 KASSERT(buflen >= sg_len, 611 ("Segment length overruns original buffer")); 612 buflen -= sg_len; 613 } 614 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 615 } 616 } 617 618 static int 619 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 620 { 621 622 /* Reserve Necessary Bounce Pages */ 623 mtx_lock(&bounce_lock); 624 if (flags & BUS_DMA_NOWAIT) { 625 if (reserve_bounce_pages(dmat, map, 0) != 0) { 626 mtx_unlock(&bounce_lock); 627 return (ENOMEM); 628 } 629 } else { 630 if (reserve_bounce_pages(dmat, map, 1) != 0) { 631 /* Queue us for resources */ 632 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 633 mtx_unlock(&bounce_lock); 634 return (EINPROGRESS); 635 } 636 } 637 mtx_unlock(&bounce_lock); 638 639 return (0); 640 } 641 642 /* 643 * Add a single contiguous physical range to the segment list. 644 */ 645 static int 646 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t curaddr, 647 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 648 { 649 bus_addr_t baddr, bmask; 650 int seg; 651 652 KASSERT(curaddr <= BUS_SPACE_MAXADDR, 653 ("ds_addr %#jx > BUS_SPACE_MAXADDR %#jx; dmat %p fl %#x low %#jx " 654 "hi %#jx", 655 (uintmax_t)curaddr, (uintmax_t)BUS_SPACE_MAXADDR, 656 dmat, dmat->bounce_flags, (uintmax_t)dmat->common.lowaddr, 657 (uintmax_t)dmat->common.highaddr)); 658 659 /* 660 * Make sure we don't cross any boundaries. 661 */ 662 bmask = ~(dmat->common.boundary - 1); 663 if (dmat->common.boundary > 0) { 664 baddr = (curaddr + dmat->common.boundary) & bmask; 665 if (sgsize > (baddr - curaddr)) 666 sgsize = (baddr - curaddr); 667 } 668 669 /* 670 * Insert chunk into a segment, coalescing with 671 * previous segment if possible. 672 */ 673 seg = *segp; 674 if (seg == -1) { 675 seg = 0; 676 segs[seg].ds_addr = curaddr; 677 segs[seg].ds_len = sgsize; 678 } else { 679 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 680 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz && 681 (dmat->common.boundary == 0 || 682 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 683 segs[seg].ds_len += sgsize; 684 else { 685 if (++seg >= dmat->common.nsegments) 686 return (0); 687 segs[seg].ds_addr = curaddr; 688 segs[seg].ds_len = sgsize; 689 } 690 } 691 *segp = seg; 692 return (sgsize); 693 } 694 695 /* 696 * Utility function to load a physical buffer. segp contains 697 * the starting segment on entrace, and the ending segment on exit. 698 */ 699 static int 700 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 701 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, 702 int *segp) 703 { 704 bus_size_t sgsize; 705 vm_paddr_t curaddr; 706 int error; 707 708 if (map == NULL) 709 map = &nobounce_dmamap; 710 711 if (segs == NULL) 712 segs = dmat->segments; 713 714 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 715 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 716 if (map->pagesneeded != 0) { 717 error = _bus_dmamap_reserve_pages(dmat, map, flags); 718 if (error) 719 return (error); 720 } 721 } 722 723 while (buflen > 0) { 724 curaddr = buf; 725 sgsize = MIN(buflen, dmat->common.maxsegsz); 726 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 727 map->pagesneeded != 0 && 728 bus_dma_run_filter(&dmat->common, curaddr)) { 729 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK)); 730 curaddr = add_bounce_page(dmat, map, 0, curaddr, 0, 731 sgsize); 732 } 733 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 734 segp); 735 if (sgsize == 0) 736 break; 737 buf += sgsize; 738 buflen -= sgsize; 739 } 740 741 /* 742 * Did we fit? 743 */ 744 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 745 } 746 747 /* 748 * Utility function to load a linear buffer. segp contains 749 * the starting segment on entrace, and the ending segment on exit. 750 */ 751 static int 752 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 753 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, 754 int *segp) 755 { 756 bus_size_t sgsize, max_sgsize; 757 vm_paddr_t curaddr; 758 vm_offset_t kvaddr, vaddr; 759 int error; 760 761 if (map == NULL) 762 map = &nobounce_dmamap; 763 764 if (segs == NULL) 765 segs = dmat->segments; 766 767 if ((dmat->bounce_flags & BUS_DMA_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 vaddr = (vm_offset_t)buf; 777 while (buflen > 0) { 778 /* 779 * Get the physical address for this segment. 780 */ 781 if (pmap == kernel_pmap) { 782 curaddr = pmap_kextract(vaddr); 783 kvaddr = vaddr; 784 } else { 785 curaddr = pmap_extract(pmap, vaddr); 786 kvaddr = 0; 787 } 788 789 /* 790 * Compute the segment size, and adjust counts. 791 */ 792 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 793 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK); 794 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 795 map->pagesneeded != 0 && 796 bus_dma_run_filter(&dmat->common, curaddr)) { 797 sgsize = roundup2(sgsize, dmat->common.alignment); 798 sgsize = MIN(sgsize, max_sgsize); 799 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr, 0, 800 sgsize); 801 } else { 802 sgsize = MIN(sgsize, max_sgsize); 803 } 804 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 805 segp); 806 if (sgsize == 0) 807 break; 808 vaddr += sgsize; 809 buflen -= sgsize; 810 } 811 812 /* 813 * Did we fit? 814 */ 815 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 816 } 817 818 static int 819 bounce_bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map, 820 struct vm_page **ma, bus_size_t buflen, int ma_offs, int flags, 821 bus_dma_segment_t *segs, int *segp) 822 { 823 vm_paddr_t paddr, next_paddr; 824 int error, page_index; 825 bus_size_t sgsize, max_sgsize; 826 827 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 828 /* 829 * If we have to keep the offset of each page this function 830 * is not suitable, switch back to bus_dmamap_load_ma_triv 831 * which is going to do the right thing in this case. 832 */ 833 error = bus_dmamap_load_ma_triv(dmat, map, ma, buflen, ma_offs, 834 flags, segs, segp); 835 return (error); 836 } 837 838 if (map == NULL) 839 map = &nobounce_dmamap; 840 841 if (segs == NULL) 842 segs = dmat->segments; 843 844 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 845 _bus_dmamap_count_ma(dmat, map, ma, ma_offs, buflen, flags); 846 if (map->pagesneeded != 0) { 847 error = _bus_dmamap_reserve_pages(dmat, map, flags); 848 if (error) 849 return (error); 850 } 851 } 852 853 page_index = 0; 854 while (buflen > 0) { 855 /* 856 * Compute the segment size, and adjust counts. 857 */ 858 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 859 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 860 sgsize = PAGE_SIZE - ma_offs; 861 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 862 map->pagesneeded != 0 && 863 bus_dma_run_filter(&dmat->common, paddr)) { 864 sgsize = roundup2(sgsize, dmat->common.alignment); 865 sgsize = MIN(sgsize, max_sgsize); 866 KASSERT((sgsize & (dmat->common.alignment - 1)) == 0, 867 ("Segment size is not aligned")); 868 /* 869 * Check if two pages of the user provided buffer 870 * are used. 871 */ 872 if ((ma_offs + sgsize) > PAGE_SIZE) 873 next_paddr = 874 VM_PAGE_TO_PHYS(ma[page_index + 1]); 875 else 876 next_paddr = 0; 877 paddr = add_bounce_page(dmat, map, 0, paddr, 878 next_paddr, sgsize); 879 } else { 880 sgsize = MIN(sgsize, max_sgsize); 881 } 882 sgsize = _bus_dmamap_addseg(dmat, map, paddr, sgsize, segs, 883 segp); 884 if (sgsize == 0) 885 break; 886 KASSERT(buflen >= sgsize, 887 ("Segment length overruns original buffer")); 888 buflen -= sgsize; 889 if (((ma_offs + sgsize) & ~PAGE_MASK) != 0) 890 page_index++; 891 ma_offs = (ma_offs + sgsize) & PAGE_MASK; 892 } 893 894 /* 895 * Did we fit? 896 */ 897 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 898 } 899 900 static void 901 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 902 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) 903 { 904 905 if (map == NULL) 906 return; 907 map->mem = *mem; 908 map->dmat = dmat; 909 map->callback = callback; 910 map->callback_arg = callback_arg; 911 } 912 913 static bus_dma_segment_t * 914 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 915 bus_dma_segment_t *segs, int nsegs, int error) 916 { 917 918 if (segs == NULL) 919 segs = dmat->segments; 920 return (segs); 921 } 922 923 /* 924 * Release the mapping held by map. 925 */ 926 static void 927 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 928 { 929 struct bounce_page *bpage; 930 931 if (map == NULL) 932 return; 933 934 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 935 STAILQ_REMOVE_HEAD(&map->bpages, links); 936 free_bounce_page(dmat, bpage); 937 } 938 } 939 940 static void 941 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, 942 bus_dmasync_op_t op) 943 { 944 struct bounce_page *bpage; 945 vm_offset_t datavaddr, tempvaddr; 946 bus_size_t datacount1, datacount2; 947 948 if (map == NULL || (bpage = STAILQ_FIRST(&map->bpages)) == NULL) 949 return; 950 951 /* 952 * Handle data bouncing. We might also want to add support for 953 * invalidating the caches on broken hardware. 954 */ 955 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 956 "performing bounce", __func__, dmat, dmat->common.flags, op); 957 958 if ((op & BUS_DMASYNC_PREWRITE) != 0) { 959 while (bpage != NULL) { 960 tempvaddr = 0; 961 datavaddr = bpage->datavaddr; 962 datacount1 = bpage->datacount; 963 if (datavaddr == 0) { 964 tempvaddr = 965 pmap_quick_enter_page(bpage->datapage[0]); 966 datavaddr = tempvaddr | bpage->dataoffs; 967 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 968 datacount1); 969 } 970 971 bcopy((void *)datavaddr, 972 (void *)bpage->vaddr, datacount1); 973 974 if (tempvaddr != 0) 975 pmap_quick_remove_page(tempvaddr); 976 977 if (bpage->datapage[1] == 0) { 978 KASSERT(datacount1 == bpage->datacount, 979 ("Mismatch between data size and provided memory space")); 980 goto next_w; 981 } 982 983 /* 984 * We are dealing with an unmapped buffer that expands 985 * over two pages. 986 */ 987 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 988 datacount2 = bpage->datacount - datacount1; 989 bcopy((void *)datavaddr, 990 (void *)(bpage->vaddr + datacount1), datacount2); 991 pmap_quick_remove_page(datavaddr); 992 993 next_w: 994 bpage = STAILQ_NEXT(bpage, links); 995 } 996 dmat->bounce_zone->total_bounced++; 997 } 998 999 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 1000 while (bpage != NULL) { 1001 tempvaddr = 0; 1002 datavaddr = bpage->datavaddr; 1003 datacount1 = bpage->datacount; 1004 if (datavaddr == 0) { 1005 tempvaddr = 1006 pmap_quick_enter_page(bpage->datapage[0]); 1007 datavaddr = tempvaddr | bpage->dataoffs; 1008 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 1009 datacount1); 1010 } 1011 1012 bcopy((void *)bpage->vaddr, (void *)datavaddr, 1013 datacount1); 1014 1015 if (tempvaddr != 0) 1016 pmap_quick_remove_page(tempvaddr); 1017 1018 if (bpage->datapage[1] == 0) { 1019 KASSERT(datacount1 == bpage->datacount, 1020 ("Mismatch between data size and provided memory space")); 1021 goto next_r; 1022 } 1023 1024 /* 1025 * We are dealing with an unmapped buffer that expands 1026 * over two pages. 1027 */ 1028 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 1029 datacount2 = bpage->datacount - datacount1; 1030 bcopy((void *)(bpage->vaddr + datacount1), 1031 (void *)datavaddr, datacount2); 1032 pmap_quick_remove_page(datavaddr); 1033 1034 next_r: 1035 bpage = STAILQ_NEXT(bpage, links); 1036 } 1037 dmat->bounce_zone->total_bounced++; 1038 } 1039 } 1040 1041 static void 1042 init_bounce_pages(void *dummy __unused) 1043 { 1044 1045 total_bpages = 0; 1046 STAILQ_INIT(&bounce_zone_list); 1047 STAILQ_INIT(&bounce_map_waitinglist); 1048 STAILQ_INIT(&bounce_map_callbacklist); 1049 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 1050 } 1051 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 1052 1053 static struct sysctl_ctx_list * 1054 busdma_sysctl_tree(struct bounce_zone *bz) 1055 { 1056 1057 return (&bz->sysctl_tree); 1058 } 1059 1060 static struct sysctl_oid * 1061 busdma_sysctl_tree_top(struct bounce_zone *bz) 1062 { 1063 1064 return (bz->sysctl_tree_top); 1065 } 1066 1067 static int 1068 alloc_bounce_zone(bus_dma_tag_t dmat) 1069 { 1070 struct bounce_zone *bz; 1071 1072 /* Check to see if we already have a suitable zone */ 1073 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1074 if (dmat->common.alignment <= bz->alignment && 1075 dmat->common.lowaddr >= bz->lowaddr && 1076 dmat->common.domain == bz->domain) { 1077 dmat->bounce_zone = bz; 1078 return (0); 1079 } 1080 } 1081 1082 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1083 M_NOWAIT | M_ZERO)) == NULL) 1084 return (ENOMEM); 1085 1086 STAILQ_INIT(&bz->bounce_page_list); 1087 bz->free_bpages = 0; 1088 bz->reserved_bpages = 0; 1089 bz->active_bpages = 0; 1090 bz->lowaddr = dmat->common.lowaddr; 1091 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE); 1092 bz->map_count = 0; 1093 bz->domain = dmat->common.domain; 1094 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1095 busdma_zonecount++; 1096 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1097 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1098 dmat->bounce_zone = bz; 1099 1100 sysctl_ctx_init(&bz->sysctl_tree); 1101 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1102 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1103 CTLFLAG_RD, 0, ""); 1104 if (bz->sysctl_tree_top == NULL) { 1105 sysctl_ctx_free(&bz->sysctl_tree); 1106 return (0); /* XXX error code? */ 1107 } 1108 1109 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1110 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1111 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1112 "Total bounce pages"); 1113 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1114 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1115 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1116 "Free bounce pages"); 1117 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1118 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1119 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1120 "Reserved bounce pages"); 1121 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1122 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1123 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1124 "Active bounce pages"); 1125 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1126 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1127 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1128 "Total bounce requests"); 1129 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1130 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1131 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1132 "Total bounce requests that were deferred"); 1133 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1134 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1135 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1136 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz), 1137 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1138 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1139 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1140 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1141 "domain", CTLFLAG_RD, &bz->domain, 0, 1142 "memory domain"); 1143 1144 return (0); 1145 } 1146 1147 static int 1148 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1149 { 1150 struct bounce_zone *bz; 1151 int count; 1152 1153 bz = dmat->bounce_zone; 1154 count = 0; 1155 while (numpages > 0) { 1156 struct bounce_page *bpage; 1157 1158 bpage = malloc_domainset(sizeof(*bpage), M_DEVBUF, 1159 DOMAINSET_PREF(dmat->common.domain), M_NOWAIT | M_ZERO); 1160 1161 if (bpage == NULL) 1162 break; 1163 bpage->vaddr = (vm_offset_t)contigmalloc_domainset(PAGE_SIZE, 1164 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), M_NOWAIT, 1165 0ul, bz->lowaddr, PAGE_SIZE, 0); 1166 if (bpage->vaddr == 0) { 1167 free_domain(bpage, M_DEVBUF); 1168 break; 1169 } 1170 bpage->busaddr = pmap_kextract(bpage->vaddr); 1171 mtx_lock(&bounce_lock); 1172 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1173 total_bpages++; 1174 bz->total_bpages++; 1175 bz->free_bpages++; 1176 mtx_unlock(&bounce_lock); 1177 count++; 1178 numpages--; 1179 } 1180 return (count); 1181 } 1182 1183 static int 1184 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1185 { 1186 struct bounce_zone *bz; 1187 int pages; 1188 1189 mtx_assert(&bounce_lock, MA_OWNED); 1190 bz = dmat->bounce_zone; 1191 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1192 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1193 return (map->pagesneeded - (map->pagesreserved + pages)); 1194 bz->free_bpages -= pages; 1195 bz->reserved_bpages += pages; 1196 map->pagesreserved += pages; 1197 pages = map->pagesneeded - map->pagesreserved; 1198 1199 return (pages); 1200 } 1201 1202 static bus_addr_t 1203 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1204 vm_paddr_t addr1, vm_paddr_t addr2, bus_size_t size) 1205 { 1206 struct bounce_zone *bz; 1207 struct bounce_page *bpage; 1208 1209 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1210 KASSERT(map != NULL && map != &nobounce_dmamap, 1211 ("add_bounce_page: bad map %p", map)); 1212 1213 bz = dmat->bounce_zone; 1214 if (map->pagesneeded == 0) 1215 panic("add_bounce_page: map doesn't need any pages"); 1216 map->pagesneeded--; 1217 1218 if (map->pagesreserved == 0) 1219 panic("add_bounce_page: map doesn't need any pages"); 1220 map->pagesreserved--; 1221 1222 mtx_lock(&bounce_lock); 1223 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1224 if (bpage == NULL) 1225 panic("add_bounce_page: free page list is empty"); 1226 1227 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1228 bz->reserved_bpages--; 1229 bz->active_bpages++; 1230 mtx_unlock(&bounce_lock); 1231 1232 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1233 /* Page offset needs to be preserved. */ 1234 bpage->vaddr |= addr1 & PAGE_MASK; 1235 bpage->busaddr |= addr1 & PAGE_MASK; 1236 KASSERT(addr2 == 0, 1237 ("Trying to bounce multiple pages with BUS_DMA_KEEP_PG_OFFSET")); 1238 } 1239 bpage->datavaddr = vaddr; 1240 bpage->datapage[0] = PHYS_TO_VM_PAGE(addr1); 1241 KASSERT((addr2 & PAGE_MASK) == 0, ("Second page is not aligned")); 1242 bpage->datapage[1] = PHYS_TO_VM_PAGE(addr2); 1243 bpage->dataoffs = addr1 & PAGE_MASK; 1244 bpage->datacount = size; 1245 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1246 return (bpage->busaddr); 1247 } 1248 1249 static void 1250 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1251 { 1252 struct bus_dmamap *map; 1253 struct bounce_zone *bz; 1254 1255 bz = dmat->bounce_zone; 1256 bpage->datavaddr = 0; 1257 bpage->datacount = 0; 1258 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1259 /* 1260 * Reset the bounce page to start at offset 0. Other uses 1261 * of this bounce page may need to store a full page of 1262 * data and/or assume it starts on a page boundary. 1263 */ 1264 bpage->vaddr &= ~PAGE_MASK; 1265 bpage->busaddr &= ~PAGE_MASK; 1266 } 1267 1268 mtx_lock(&bounce_lock); 1269 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1270 bz->free_bpages++; 1271 bz->active_bpages--; 1272 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1273 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1274 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1275 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1276 map, links); 1277 busdma_swi_pending = 1; 1278 bz->total_deferred++; 1279 swi_sched(vm_ih, 0); 1280 } 1281 } 1282 mtx_unlock(&bounce_lock); 1283 } 1284 1285 void 1286 busdma_swi(void) 1287 { 1288 bus_dma_tag_t dmat; 1289 struct bus_dmamap *map; 1290 1291 mtx_lock(&bounce_lock); 1292 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1293 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1294 mtx_unlock(&bounce_lock); 1295 dmat = map->dmat; 1296 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK); 1297 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1298 map->callback, map->callback_arg, BUS_DMA_WAITOK); 1299 (dmat->common.lockfunc)(dmat->common.lockfuncarg, 1300 BUS_DMA_UNLOCK); 1301 mtx_lock(&bounce_lock); 1302 } 1303 mtx_unlock(&bounce_lock); 1304 } 1305 1306 struct bus_dma_impl bus_dma_bounce_impl = { 1307 .tag_create = bounce_bus_dma_tag_create, 1308 .tag_destroy = bounce_bus_dma_tag_destroy, 1309 .tag_set_domain = bounce_bus_dma_tag_set_domain, 1310 .map_create = bounce_bus_dmamap_create, 1311 .map_destroy = bounce_bus_dmamap_destroy, 1312 .mem_alloc = bounce_bus_dmamem_alloc, 1313 .mem_free = bounce_bus_dmamem_free, 1314 .load_phys = bounce_bus_dmamap_load_phys, 1315 .load_buffer = bounce_bus_dmamap_load_buffer, 1316 .load_ma = bounce_bus_dmamap_load_ma, 1317 .map_waitok = bounce_bus_dmamap_waitok, 1318 .map_complete = bounce_bus_dmamap_complete, 1319 .map_unload = bounce_bus_dmamap_unload, 1320 .map_sync = bounce_bus_dmamap_sync, 1321 }; 1322