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 | CTLFLAG_MPSAFE, 0, 118 "Busdma parameters"); 119 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 120 "Total bounce pages"); 121 122 struct bus_dmamap { 123 struct bp_list bpages; 124 int pagesneeded; 125 int pagesreserved; 126 bus_dma_tag_t dmat; 127 struct memdesc mem; 128 bus_dmamap_callback_t *callback; 129 void *callback_arg; 130 STAILQ_ENTRY(bus_dmamap) links; 131 }; 132 133 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 134 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 135 static struct bus_dmamap nobounce_dmamap; 136 137 static void init_bounce_pages(void *dummy); 138 static int alloc_bounce_zone(bus_dma_tag_t dmat); 139 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 140 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 141 int commit); 142 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 143 vm_offset_t vaddr, vm_paddr_t addr1, vm_paddr_t addr2, bus_size_t size); 144 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 145 static bool _bus_dmamap_pagesneeded(bus_dma_tag_t dmat, vm_paddr_t buf, 146 bus_size_t buflen, int *pagesneeded); 147 static void _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 148 pmap_t pmap, void *buf, bus_size_t buflen, int flags); 149 static void _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 150 vm_paddr_t buf, bus_size_t buflen, 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 static bool 230 bounce_bus_dma_id_mapped(bus_dma_tag_t dmat, vm_paddr_t buf, bus_size_t buflen) 231 { 232 233 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) == 0) 234 return (true); 235 return (!_bus_dmamap_pagesneeded(dmat, buf, buflen, NULL)); 236 } 237 238 /* 239 * Update the domain for the tag. We may need to reallocate the zone and 240 * bounce pages. 241 */ 242 static int 243 bounce_bus_dma_tag_set_domain(bus_dma_tag_t dmat) 244 { 245 246 KASSERT(dmat->map_count == 0, 247 ("bounce_bus_dma_tag_set_domain: Domain set after use.\n")); 248 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) == 0 || 249 dmat->bounce_zone == NULL) 250 return (0); 251 dmat->bounce_flags &= ~BUS_DMA_MIN_ALLOC_COMP; 252 return (bounce_bus_dma_zone_setup(dmat)); 253 } 254 255 static int 256 bounce_bus_dma_tag_destroy(bus_dma_tag_t dmat) 257 { 258 bus_dma_tag_t dmat_copy, parent; 259 int error; 260 261 error = 0; 262 dmat_copy = dmat; 263 264 if (dmat != NULL) { 265 if (dmat->map_count != 0) { 266 error = EBUSY; 267 goto out; 268 } 269 while (dmat != NULL) { 270 parent = (bus_dma_tag_t)dmat->common.parent; 271 atomic_subtract_int(&dmat->common.ref_count, 1); 272 if (dmat->common.ref_count == 0) { 273 if (dmat->segments != NULL) 274 free_domain(dmat->segments, M_DEVBUF); 275 free(dmat, M_DEVBUF); 276 /* 277 * Last reference count, so 278 * release our reference 279 * count on our parent. 280 */ 281 dmat = parent; 282 } else 283 dmat = NULL; 284 } 285 } 286 out: 287 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 288 return (error); 289 } 290 291 /* 292 * Allocate a handle for mapping from kva/uva/physical 293 * address space into bus device space. 294 */ 295 static int 296 bounce_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 297 { 298 struct bounce_zone *bz; 299 int error, maxpages, pages; 300 301 error = 0; 302 303 if (dmat->segments == NULL) { 304 dmat->segments = (bus_dma_segment_t *)malloc_domainset( 305 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 306 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), M_NOWAIT); 307 if (dmat->segments == NULL) { 308 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 309 __func__, dmat, ENOMEM); 310 return (ENOMEM); 311 } 312 } 313 314 /* 315 * Bouncing might be required if the driver asks for an active 316 * exclusion region, a data alignment that is stricter than 1, and/or 317 * an active address boundary. 318 */ 319 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 320 /* Must bounce */ 321 if (dmat->bounce_zone == NULL) { 322 if ((error = alloc_bounce_zone(dmat)) != 0) 323 return (error); 324 } 325 bz = dmat->bounce_zone; 326 327 *mapp = (bus_dmamap_t)malloc_domainset(sizeof(**mapp), M_DEVBUF, 328 DOMAINSET_PREF(dmat->common.domain), M_NOWAIT | M_ZERO); 329 if (*mapp == NULL) { 330 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 331 __func__, dmat, ENOMEM); 332 return (ENOMEM); 333 } 334 335 /* Initialize the new map */ 336 STAILQ_INIT(&((*mapp)->bpages)); 337 338 /* 339 * Attempt to add pages to our pool on a per-instance 340 * basis up to a sane limit. 341 */ 342 if (dmat->common.alignment > 1) 343 maxpages = MAX_BPAGES; 344 else 345 maxpages = MIN(MAX_BPAGES, Maxmem - 346 atop(dmat->common.lowaddr)); 347 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) == 0 || 348 (bz->map_count > 0 && bz->total_bpages < maxpages)) { 349 pages = MAX(atop(dmat->common.maxsize), 1); 350 pages = MIN(maxpages - bz->total_bpages, pages); 351 pages = MAX(pages, 1); 352 if (alloc_bounce_pages(dmat, pages) < pages) 353 error = ENOMEM; 354 if ((dmat->bounce_flags & BUS_DMA_MIN_ALLOC_COMP) 355 == 0) { 356 if (error == 0) { 357 dmat->bounce_flags |= 358 BUS_DMA_MIN_ALLOC_COMP; 359 } 360 } else 361 error = 0; 362 } 363 bz->map_count++; 364 } else { 365 *mapp = NULL; 366 } 367 if (error == 0) 368 dmat->map_count++; 369 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 370 __func__, dmat, dmat->common.flags, error); 371 return (error); 372 } 373 374 /* 375 * Destroy a handle for mapping from kva/uva/physical 376 * address space into bus device space. 377 */ 378 static int 379 bounce_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 380 { 381 382 if (map != NULL && map != &nobounce_dmamap) { 383 if (STAILQ_FIRST(&map->bpages) != NULL) { 384 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 385 __func__, dmat, EBUSY); 386 return (EBUSY); 387 } 388 if (dmat->bounce_zone) 389 dmat->bounce_zone->map_count--; 390 free_domain(map, M_DEVBUF); 391 } 392 dmat->map_count--; 393 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 394 return (0); 395 } 396 397 398 /* 399 * Allocate a piece of memory that can be efficiently mapped into 400 * bus device space based on the constraints lited in the dma tag. 401 * A dmamap to for use with dmamap_load is also allocated. 402 */ 403 static int 404 bounce_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 405 bus_dmamap_t *mapp) 406 { 407 vm_memattr_t attr; 408 int mflags; 409 410 if (flags & BUS_DMA_NOWAIT) 411 mflags = M_NOWAIT; 412 else 413 mflags = M_WAITOK; 414 415 /* If we succeed, no mapping/bouncing will be required */ 416 *mapp = NULL; 417 418 if (dmat->segments == NULL) { 419 dmat->segments = (bus_dma_segment_t *)malloc_domainset( 420 sizeof(bus_dma_segment_t) * dmat->common.nsegments, 421 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), mflags); 422 if (dmat->segments == NULL) { 423 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 424 __func__, dmat, dmat->common.flags, ENOMEM); 425 return (ENOMEM); 426 } 427 } 428 if (flags & BUS_DMA_ZERO) 429 mflags |= M_ZERO; 430 if (flags & BUS_DMA_NOCACHE) 431 attr = VM_MEMATTR_UNCACHEABLE; 432 else 433 attr = VM_MEMATTR_DEFAULT; 434 435 /* 436 * Allocate the buffer from the malloc(9) allocator if... 437 * - It's small enough to fit into a single power of two sized bucket. 438 * - The alignment is less than or equal to the maximum size 439 * - The low address requirement is fulfilled. 440 * else allocate non-contiguous pages if... 441 * - The page count that could get allocated doesn't exceed 442 * nsegments also when the maximum segment size is less 443 * than PAGE_SIZE. 444 * - The alignment constraint isn't larger than a page boundary. 445 * - There are no boundary-crossing constraints. 446 * else allocate a block of contiguous pages because one or more of the 447 * constraints is something that only the contig allocator can fulfill. 448 * 449 * NOTE: The (dmat->common.alignment <= dmat->maxsize) check 450 * below is just a quick hack. The exact alignment guarantees 451 * of malloc(9) need to be nailed down, and the code below 452 * should be rewritten to take that into account. 453 * 454 * In the meantime warn the user if malloc gets it wrong. 455 */ 456 if (dmat->common.maxsize <= PAGE_SIZE && 457 dmat->common.alignment <= dmat->common.maxsize && 458 dmat->common.lowaddr >= ptoa((vm_paddr_t)Maxmem) && 459 attr == VM_MEMATTR_DEFAULT) { 460 *vaddr = malloc_domainset(dmat->common.maxsize, M_DEVBUF, 461 DOMAINSET_PREF(dmat->common.domain), mflags); 462 } else if (dmat->common.nsegments >= 463 howmany(dmat->common.maxsize, MIN(dmat->common.maxsegsz, 464 PAGE_SIZE)) && 465 dmat->common.alignment <= PAGE_SIZE && 466 (dmat->common.boundary % PAGE_SIZE) == 0) { 467 /* Page-based multi-segment allocations allowed */ 468 *vaddr = (void *)kmem_alloc_attr_domainset( 469 DOMAINSET_PREF(dmat->common.domain), dmat->common.maxsize, 470 mflags, 0ul, dmat->common.lowaddr, attr); 471 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 472 } else { 473 *vaddr = (void *)kmem_alloc_contig_domainset( 474 DOMAINSET_PREF(dmat->common.domain), dmat->common.maxsize, 475 mflags, 0ul, dmat->common.lowaddr, 476 dmat->common.alignment != 0 ? dmat->common.alignment : 1ul, 477 dmat->common.boundary, attr); 478 dmat->bounce_flags |= BUS_DMA_KMEM_ALLOC; 479 } 480 if (*vaddr == NULL) { 481 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 482 __func__, dmat, dmat->common.flags, ENOMEM); 483 return (ENOMEM); 484 } else if (vtophys(*vaddr) & (dmat->common.alignment - 1)) { 485 printf("bus_dmamem_alloc failed to align memory properly.\n"); 486 } 487 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 488 __func__, dmat, dmat->common.flags, 0); 489 return (0); 490 } 491 492 /* 493 * Free a piece of memory and its associated dmamap, that was allocated 494 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 495 */ 496 static void 497 bounce_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 498 { 499 /* 500 * dmamem does not need to be bounced, so the map should be 501 * NULL and the BUS_DMA_KMEM_ALLOC flag cleared if malloc() 502 * was used and set if kmem_alloc_contig() was used. 503 */ 504 if (map != NULL) 505 panic("bus_dmamem_free: Invalid map freed\n"); 506 if ((dmat->bounce_flags & BUS_DMA_KMEM_ALLOC) == 0) 507 free_domain(vaddr, M_DEVBUF); 508 else 509 kmem_free((vm_offset_t)vaddr, dmat->common.maxsize); 510 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, 511 dmat->bounce_flags); 512 } 513 514 static bool 515 _bus_dmamap_pagesneeded(bus_dma_tag_t dmat, vm_paddr_t buf, bus_size_t buflen, 516 int *pagesneeded) 517 { 518 vm_paddr_t curaddr; 519 bus_size_t sgsize; 520 int count; 521 522 /* 523 * Count the number of bounce pages needed in order to 524 * complete this transfer 525 */ 526 count = 0; 527 curaddr = buf; 528 while (buflen != 0) { 529 sgsize = MIN(buflen, dmat->common.maxsegsz); 530 if (bus_dma_run_filter(&dmat->common, curaddr)) { 531 sgsize = MIN(sgsize, 532 PAGE_SIZE - (curaddr & PAGE_MASK)); 533 if (pagesneeded == NULL) 534 return (true); 535 count++; 536 } 537 curaddr += sgsize; 538 buflen -= sgsize; 539 } 540 541 if (pagesneeded != NULL) 542 *pagesneeded = count; 543 return (count != 0); 544 } 545 546 static void 547 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf, 548 bus_size_t buflen, int flags) 549 { 550 551 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 552 _bus_dmamap_pagesneeded(dmat, buf, buflen, &map->pagesneeded); 553 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 554 } 555 } 556 557 static void 558 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 559 void *buf, bus_size_t buflen, int flags) 560 { 561 vm_offset_t vaddr; 562 vm_offset_t vendaddr; 563 vm_paddr_t paddr; 564 bus_size_t sg_len; 565 566 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 567 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 568 "alignment= %d", dmat->common.lowaddr, 569 ptoa((vm_paddr_t)Maxmem), 570 dmat->common.boundary, dmat->common.alignment); 571 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 572 map, &nobounce_dmamap, map->pagesneeded); 573 /* 574 * Count the number of bounce pages 575 * needed in order to complete this transfer 576 */ 577 vaddr = (vm_offset_t)buf; 578 vendaddr = (vm_offset_t)buf + buflen; 579 580 while (vaddr < vendaddr) { 581 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 582 if (pmap == kernel_pmap) 583 paddr = pmap_kextract(vaddr); 584 else 585 paddr = pmap_extract(pmap, vaddr); 586 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 587 sg_len = roundup2(sg_len, 588 dmat->common.alignment); 589 map->pagesneeded++; 590 } 591 vaddr += sg_len; 592 } 593 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 594 } 595 } 596 597 static void 598 _bus_dmamap_count_ma(bus_dma_tag_t dmat, bus_dmamap_t map, struct vm_page **ma, 599 int ma_offs, bus_size_t buflen, int flags) 600 { 601 bus_size_t sg_len, max_sgsize; 602 int page_index; 603 vm_paddr_t paddr; 604 605 if (map != &nobounce_dmamap && map->pagesneeded == 0) { 606 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 607 "alignment= %d", dmat->common.lowaddr, 608 ptoa((vm_paddr_t)Maxmem), 609 dmat->common.boundary, dmat->common.alignment); 610 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 611 map, &nobounce_dmamap, map->pagesneeded); 612 613 /* 614 * Count the number of bounce pages 615 * needed in order to complete this transfer 616 */ 617 page_index = 0; 618 while (buflen > 0) { 619 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 620 sg_len = PAGE_SIZE - ma_offs; 621 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 622 sg_len = MIN(sg_len, max_sgsize); 623 if (bus_dma_run_filter(&dmat->common, paddr) != 0) { 624 sg_len = roundup2(sg_len, 625 dmat->common.alignment); 626 sg_len = MIN(sg_len, max_sgsize); 627 KASSERT((sg_len & (dmat->common.alignment - 1)) 628 == 0, ("Segment size is not aligned")); 629 map->pagesneeded++; 630 } 631 if (((ma_offs + sg_len) & ~PAGE_MASK) != 0) 632 page_index++; 633 ma_offs = (ma_offs + sg_len) & PAGE_MASK; 634 KASSERT(buflen >= sg_len, 635 ("Segment length overruns original buffer")); 636 buflen -= sg_len; 637 } 638 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 639 } 640 } 641 642 static int 643 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags) 644 { 645 646 /* Reserve Necessary Bounce Pages */ 647 mtx_lock(&bounce_lock); 648 if (flags & BUS_DMA_NOWAIT) { 649 if (reserve_bounce_pages(dmat, map, 0) != 0) { 650 mtx_unlock(&bounce_lock); 651 return (ENOMEM); 652 } 653 } else { 654 if (reserve_bounce_pages(dmat, map, 1) != 0) { 655 /* Queue us for resources */ 656 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links); 657 mtx_unlock(&bounce_lock); 658 return (EINPROGRESS); 659 } 660 } 661 mtx_unlock(&bounce_lock); 662 663 return (0); 664 } 665 666 /* 667 * Add a single contiguous physical range to the segment list. 668 */ 669 static bus_size_t 670 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t curaddr, 671 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp) 672 { 673 bus_addr_t baddr, bmask; 674 int seg; 675 676 KASSERT(curaddr <= BUS_SPACE_MAXADDR, 677 ("ds_addr %#jx > BUS_SPACE_MAXADDR %#jx; dmat %p fl %#x low %#jx " 678 "hi %#jx", 679 (uintmax_t)curaddr, (uintmax_t)BUS_SPACE_MAXADDR, 680 dmat, dmat->bounce_flags, (uintmax_t)dmat->common.lowaddr, 681 (uintmax_t)dmat->common.highaddr)); 682 683 /* 684 * Make sure we don't cross any boundaries. 685 */ 686 bmask = ~(dmat->common.boundary - 1); 687 if (dmat->common.boundary > 0) { 688 baddr = (curaddr + dmat->common.boundary) & bmask; 689 if (sgsize > (baddr - curaddr)) 690 sgsize = (baddr - curaddr); 691 } 692 693 /* 694 * Insert chunk into a segment, coalescing with 695 * previous segment if possible. 696 */ 697 seg = *segp; 698 if (seg == -1) { 699 seg = 0; 700 segs[seg].ds_addr = curaddr; 701 segs[seg].ds_len = sgsize; 702 } else { 703 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len && 704 (segs[seg].ds_len + sgsize) <= dmat->common.maxsegsz && 705 (dmat->common.boundary == 0 || 706 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 707 segs[seg].ds_len += sgsize; 708 else { 709 if (++seg >= dmat->common.nsegments) 710 return (0); 711 segs[seg].ds_addr = curaddr; 712 segs[seg].ds_len = sgsize; 713 } 714 } 715 *segp = seg; 716 return (sgsize); 717 } 718 719 /* 720 * Utility function to load a physical buffer. segp contains 721 * the starting segment on entrace, and the ending segment on exit. 722 */ 723 static int 724 bounce_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, 725 vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, 726 int *segp) 727 { 728 bus_size_t sgsize; 729 vm_paddr_t curaddr; 730 int error; 731 732 if (map == NULL) 733 map = &nobounce_dmamap; 734 735 if (segs == NULL) 736 segs = dmat->segments; 737 738 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 739 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags); 740 if (map->pagesneeded != 0) { 741 error = _bus_dmamap_reserve_pages(dmat, map, flags); 742 if (error) 743 return (error); 744 } 745 } 746 747 while (buflen > 0) { 748 curaddr = buf; 749 sgsize = MIN(buflen, dmat->common.maxsegsz); 750 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 751 map->pagesneeded != 0 && 752 bus_dma_run_filter(&dmat->common, curaddr)) { 753 sgsize = MIN(sgsize, PAGE_SIZE - (curaddr & PAGE_MASK)); 754 curaddr = add_bounce_page(dmat, map, 0, curaddr, 0, 755 sgsize); 756 } 757 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 758 segp); 759 if (sgsize == 0) 760 break; 761 buf += sgsize; 762 buflen -= sgsize; 763 } 764 765 /* 766 * Did we fit? 767 */ 768 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 769 } 770 771 /* 772 * Utility function to load a linear buffer. segp contains 773 * the starting segment on entrace, and the ending segment on exit. 774 */ 775 static int 776 bounce_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 777 bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, 778 int *segp) 779 { 780 bus_size_t sgsize, max_sgsize; 781 vm_paddr_t curaddr; 782 vm_offset_t kvaddr, vaddr; 783 int error; 784 785 if (map == NULL) 786 map = &nobounce_dmamap; 787 788 if (segs == NULL) 789 segs = dmat->segments; 790 791 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 792 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 793 if (map->pagesneeded != 0) { 794 error = _bus_dmamap_reserve_pages(dmat, map, flags); 795 if (error) 796 return (error); 797 } 798 } 799 800 vaddr = (vm_offset_t)buf; 801 while (buflen > 0) { 802 /* 803 * Get the physical address for this segment. 804 */ 805 if (pmap == kernel_pmap) { 806 curaddr = pmap_kextract(vaddr); 807 kvaddr = vaddr; 808 } else { 809 curaddr = pmap_extract(pmap, vaddr); 810 kvaddr = 0; 811 } 812 813 /* 814 * Compute the segment size, and adjust counts. 815 */ 816 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 817 sgsize = PAGE_SIZE - (curaddr & PAGE_MASK); 818 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 819 map->pagesneeded != 0 && 820 bus_dma_run_filter(&dmat->common, curaddr)) { 821 sgsize = roundup2(sgsize, dmat->common.alignment); 822 sgsize = MIN(sgsize, max_sgsize); 823 curaddr = add_bounce_page(dmat, map, kvaddr, curaddr, 0, 824 sgsize); 825 } else { 826 sgsize = MIN(sgsize, max_sgsize); 827 } 828 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs, 829 segp); 830 if (sgsize == 0) 831 break; 832 vaddr += sgsize; 833 buflen -= sgsize; 834 } 835 836 /* 837 * Did we fit? 838 */ 839 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 840 } 841 842 static int 843 bounce_bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map, 844 struct vm_page **ma, bus_size_t buflen, int ma_offs, int flags, 845 bus_dma_segment_t *segs, int *segp) 846 { 847 vm_paddr_t paddr, next_paddr; 848 int error, page_index; 849 bus_size_t sgsize, max_sgsize; 850 851 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 852 /* 853 * If we have to keep the offset of each page this function 854 * is not suitable, switch back to bus_dmamap_load_ma_triv 855 * which is going to do the right thing in this case. 856 */ 857 error = bus_dmamap_load_ma_triv(dmat, map, ma, buflen, ma_offs, 858 flags, segs, segp); 859 return (error); 860 } 861 862 if (map == NULL) 863 map = &nobounce_dmamap; 864 865 if (segs == NULL) 866 segs = dmat->segments; 867 868 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0) { 869 _bus_dmamap_count_ma(dmat, map, ma, ma_offs, buflen, flags); 870 if (map->pagesneeded != 0) { 871 error = _bus_dmamap_reserve_pages(dmat, map, flags); 872 if (error) 873 return (error); 874 } 875 } 876 877 page_index = 0; 878 while (buflen > 0) { 879 /* 880 * Compute the segment size, and adjust counts. 881 */ 882 paddr = VM_PAGE_TO_PHYS(ma[page_index]) + ma_offs; 883 max_sgsize = MIN(buflen, dmat->common.maxsegsz); 884 sgsize = PAGE_SIZE - ma_offs; 885 if ((dmat->bounce_flags & BUS_DMA_COULD_BOUNCE) != 0 && 886 map->pagesneeded != 0 && 887 bus_dma_run_filter(&dmat->common, paddr)) { 888 sgsize = roundup2(sgsize, dmat->common.alignment); 889 sgsize = MIN(sgsize, max_sgsize); 890 KASSERT((sgsize & (dmat->common.alignment - 1)) == 0, 891 ("Segment size is not aligned")); 892 /* 893 * Check if two pages of the user provided buffer 894 * are used. 895 */ 896 if ((ma_offs + sgsize) > PAGE_SIZE) 897 next_paddr = 898 VM_PAGE_TO_PHYS(ma[page_index + 1]); 899 else 900 next_paddr = 0; 901 paddr = add_bounce_page(dmat, map, 0, paddr, 902 next_paddr, sgsize); 903 } else { 904 sgsize = MIN(sgsize, max_sgsize); 905 } 906 sgsize = _bus_dmamap_addseg(dmat, map, paddr, sgsize, segs, 907 segp); 908 if (sgsize == 0) 909 break; 910 KASSERT(buflen >= sgsize, 911 ("Segment length overruns original buffer")); 912 buflen -= sgsize; 913 if (((ma_offs + sgsize) & ~PAGE_MASK) != 0) 914 page_index++; 915 ma_offs = (ma_offs + sgsize) & PAGE_MASK; 916 } 917 918 /* 919 * Did we fit? 920 */ 921 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 922 } 923 924 static void 925 bounce_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map, 926 struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) 927 { 928 929 if (map == NULL) 930 return; 931 map->mem = *mem; 932 map->dmat = dmat; 933 map->callback = callback; 934 map->callback_arg = callback_arg; 935 } 936 937 static bus_dma_segment_t * 938 bounce_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map, 939 bus_dma_segment_t *segs, int nsegs, int error) 940 { 941 942 if (segs == NULL) 943 segs = dmat->segments; 944 return (segs); 945 } 946 947 /* 948 * Release the mapping held by map. 949 */ 950 static void 951 bounce_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 952 { 953 struct bounce_page *bpage; 954 955 if (map == NULL) 956 return; 957 958 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 959 STAILQ_REMOVE_HEAD(&map->bpages, links); 960 free_bounce_page(dmat, bpage); 961 } 962 } 963 964 static void 965 bounce_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, 966 bus_dmasync_op_t op) 967 { 968 struct bounce_page *bpage; 969 vm_offset_t datavaddr, tempvaddr; 970 bus_size_t datacount1, datacount2; 971 972 if (map == NULL || (bpage = STAILQ_FIRST(&map->bpages)) == NULL) 973 return; 974 975 /* 976 * Handle data bouncing. We might also want to add support for 977 * invalidating the caches on broken hardware. 978 */ 979 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 980 "performing bounce", __func__, dmat, dmat->common.flags, op); 981 982 if ((op & BUS_DMASYNC_PREWRITE) != 0) { 983 while (bpage != NULL) { 984 tempvaddr = 0; 985 datavaddr = bpage->datavaddr; 986 datacount1 = bpage->datacount; 987 if (datavaddr == 0) { 988 tempvaddr = 989 pmap_quick_enter_page(bpage->datapage[0]); 990 datavaddr = tempvaddr | bpage->dataoffs; 991 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 992 datacount1); 993 } 994 995 bcopy((void *)datavaddr, 996 (void *)bpage->vaddr, datacount1); 997 998 if (tempvaddr != 0) 999 pmap_quick_remove_page(tempvaddr); 1000 1001 if (bpage->datapage[1] == 0) { 1002 KASSERT(datacount1 == bpage->datacount, 1003 ("Mismatch between data size and provided memory space")); 1004 goto next_w; 1005 } 1006 1007 /* 1008 * We are dealing with an unmapped buffer that expands 1009 * over two pages. 1010 */ 1011 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 1012 datacount2 = bpage->datacount - datacount1; 1013 bcopy((void *)datavaddr, 1014 (void *)(bpage->vaddr + datacount1), datacount2); 1015 pmap_quick_remove_page(datavaddr); 1016 1017 next_w: 1018 bpage = STAILQ_NEXT(bpage, links); 1019 } 1020 dmat->bounce_zone->total_bounced++; 1021 } 1022 1023 if ((op & BUS_DMASYNC_POSTREAD) != 0) { 1024 while (bpage != NULL) { 1025 tempvaddr = 0; 1026 datavaddr = bpage->datavaddr; 1027 datacount1 = bpage->datacount; 1028 if (datavaddr == 0) { 1029 tempvaddr = 1030 pmap_quick_enter_page(bpage->datapage[0]); 1031 datavaddr = tempvaddr | bpage->dataoffs; 1032 datacount1 = min(PAGE_SIZE - bpage->dataoffs, 1033 datacount1); 1034 } 1035 1036 bcopy((void *)bpage->vaddr, (void *)datavaddr, 1037 datacount1); 1038 1039 if (tempvaddr != 0) 1040 pmap_quick_remove_page(tempvaddr); 1041 1042 if (bpage->datapage[1] == 0) { 1043 KASSERT(datacount1 == bpage->datacount, 1044 ("Mismatch between data size and provided memory space")); 1045 goto next_r; 1046 } 1047 1048 /* 1049 * We are dealing with an unmapped buffer that expands 1050 * over two pages. 1051 */ 1052 datavaddr = pmap_quick_enter_page(bpage->datapage[1]); 1053 datacount2 = bpage->datacount - datacount1; 1054 bcopy((void *)(bpage->vaddr + datacount1), 1055 (void *)datavaddr, datacount2); 1056 pmap_quick_remove_page(datavaddr); 1057 1058 next_r: 1059 bpage = STAILQ_NEXT(bpage, links); 1060 } 1061 dmat->bounce_zone->total_bounced++; 1062 } 1063 } 1064 1065 static void 1066 init_bounce_pages(void *dummy __unused) 1067 { 1068 1069 total_bpages = 0; 1070 STAILQ_INIT(&bounce_zone_list); 1071 STAILQ_INIT(&bounce_map_waitinglist); 1072 STAILQ_INIT(&bounce_map_callbacklist); 1073 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 1074 } 1075 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 1076 1077 static struct sysctl_ctx_list * 1078 busdma_sysctl_tree(struct bounce_zone *bz) 1079 { 1080 1081 return (&bz->sysctl_tree); 1082 } 1083 1084 static struct sysctl_oid * 1085 busdma_sysctl_tree_top(struct bounce_zone *bz) 1086 { 1087 1088 return (bz->sysctl_tree_top); 1089 } 1090 1091 static int 1092 alloc_bounce_zone(bus_dma_tag_t dmat) 1093 { 1094 struct bounce_zone *bz; 1095 1096 /* Check to see if we already have a suitable zone */ 1097 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1098 if (dmat->common.alignment <= bz->alignment && 1099 dmat->common.lowaddr >= bz->lowaddr && 1100 dmat->common.domain == bz->domain) { 1101 dmat->bounce_zone = bz; 1102 return (0); 1103 } 1104 } 1105 1106 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1107 M_NOWAIT | M_ZERO)) == NULL) 1108 return (ENOMEM); 1109 1110 STAILQ_INIT(&bz->bounce_page_list); 1111 bz->free_bpages = 0; 1112 bz->reserved_bpages = 0; 1113 bz->active_bpages = 0; 1114 bz->lowaddr = dmat->common.lowaddr; 1115 bz->alignment = MAX(dmat->common.alignment, PAGE_SIZE); 1116 bz->map_count = 0; 1117 bz->domain = dmat->common.domain; 1118 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1119 busdma_zonecount++; 1120 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1121 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1122 dmat->bounce_zone = bz; 1123 1124 sysctl_ctx_init(&bz->sysctl_tree); 1125 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1126 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1127 CTLFLAG_RD | CTLFLAG_MPSAFE, 0, ""); 1128 if (bz->sysctl_tree_top == NULL) { 1129 sysctl_ctx_free(&bz->sysctl_tree); 1130 return (0); /* XXX error code? */ 1131 } 1132 1133 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1134 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1135 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1136 "Total bounce pages"); 1137 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1138 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1139 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1140 "Free bounce pages"); 1141 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1142 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1143 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1144 "Reserved bounce pages"); 1145 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1146 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1147 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1148 "Active bounce pages"); 1149 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1150 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1151 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1152 "Total bounce requests"); 1153 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1154 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1155 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1156 "Total bounce requests that were deferred"); 1157 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1158 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1159 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1160 SYSCTL_ADD_UAUTO(busdma_sysctl_tree(bz), 1161 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1162 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1163 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1164 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1165 "domain", CTLFLAG_RD, &bz->domain, 0, 1166 "memory domain"); 1167 1168 return (0); 1169 } 1170 1171 static int 1172 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1173 { 1174 struct bounce_zone *bz; 1175 int count; 1176 1177 bz = dmat->bounce_zone; 1178 count = 0; 1179 while (numpages > 0) { 1180 struct bounce_page *bpage; 1181 1182 bpage = malloc_domainset(sizeof(*bpage), M_DEVBUF, 1183 DOMAINSET_PREF(dmat->common.domain), M_NOWAIT | M_ZERO); 1184 1185 if (bpage == NULL) 1186 break; 1187 bpage->vaddr = (vm_offset_t)contigmalloc_domainset(PAGE_SIZE, 1188 M_DEVBUF, DOMAINSET_PREF(dmat->common.domain), M_NOWAIT, 1189 0ul, bz->lowaddr, PAGE_SIZE, 0); 1190 if (bpage->vaddr == 0) { 1191 free_domain(bpage, M_DEVBUF); 1192 break; 1193 } 1194 bpage->busaddr = pmap_kextract(bpage->vaddr); 1195 mtx_lock(&bounce_lock); 1196 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1197 total_bpages++; 1198 bz->total_bpages++; 1199 bz->free_bpages++; 1200 mtx_unlock(&bounce_lock); 1201 count++; 1202 numpages--; 1203 } 1204 return (count); 1205 } 1206 1207 static int 1208 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1209 { 1210 struct bounce_zone *bz; 1211 int pages; 1212 1213 mtx_assert(&bounce_lock, MA_OWNED); 1214 bz = dmat->bounce_zone; 1215 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1216 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1217 return (map->pagesneeded - (map->pagesreserved + pages)); 1218 bz->free_bpages -= pages; 1219 bz->reserved_bpages += pages; 1220 map->pagesreserved += pages; 1221 pages = map->pagesneeded - map->pagesreserved; 1222 1223 return (pages); 1224 } 1225 1226 static bus_addr_t 1227 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1228 vm_paddr_t addr1, vm_paddr_t addr2, bus_size_t size) 1229 { 1230 struct bounce_zone *bz; 1231 struct bounce_page *bpage; 1232 1233 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1234 KASSERT(map != NULL && map != &nobounce_dmamap, 1235 ("add_bounce_page: bad map %p", map)); 1236 1237 bz = dmat->bounce_zone; 1238 if (map->pagesneeded == 0) 1239 panic("add_bounce_page: map doesn't need any pages"); 1240 map->pagesneeded--; 1241 1242 if (map->pagesreserved == 0) 1243 panic("add_bounce_page: map doesn't need any pages"); 1244 map->pagesreserved--; 1245 1246 mtx_lock(&bounce_lock); 1247 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1248 if (bpage == NULL) 1249 panic("add_bounce_page: free page list is empty"); 1250 1251 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1252 bz->reserved_bpages--; 1253 bz->active_bpages++; 1254 mtx_unlock(&bounce_lock); 1255 1256 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1257 /* Page offset needs to be preserved. */ 1258 bpage->vaddr |= addr1 & PAGE_MASK; 1259 bpage->busaddr |= addr1 & PAGE_MASK; 1260 KASSERT(addr2 == 0, 1261 ("Trying to bounce multiple pages with BUS_DMA_KEEP_PG_OFFSET")); 1262 } 1263 bpage->datavaddr = vaddr; 1264 bpage->datapage[0] = PHYS_TO_VM_PAGE(addr1); 1265 KASSERT((addr2 & PAGE_MASK) == 0, ("Second page is not aligned")); 1266 bpage->datapage[1] = PHYS_TO_VM_PAGE(addr2); 1267 bpage->dataoffs = addr1 & PAGE_MASK; 1268 bpage->datacount = size; 1269 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1270 return (bpage->busaddr); 1271 } 1272 1273 static void 1274 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1275 { 1276 struct bus_dmamap *map; 1277 struct bounce_zone *bz; 1278 1279 bz = dmat->bounce_zone; 1280 bpage->datavaddr = 0; 1281 bpage->datacount = 0; 1282 if (dmat->common.flags & BUS_DMA_KEEP_PG_OFFSET) { 1283 /* 1284 * Reset the bounce page to start at offset 0. Other uses 1285 * of this bounce page may need to store a full page of 1286 * data and/or assume it starts on a page boundary. 1287 */ 1288 bpage->vaddr &= ~PAGE_MASK; 1289 bpage->busaddr &= ~PAGE_MASK; 1290 } 1291 1292 mtx_lock(&bounce_lock); 1293 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1294 bz->free_bpages++; 1295 bz->active_bpages--; 1296 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1297 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1298 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1299 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1300 map, links); 1301 busdma_swi_pending = 1; 1302 bz->total_deferred++; 1303 swi_sched(vm_ih, 0); 1304 } 1305 } 1306 mtx_unlock(&bounce_lock); 1307 } 1308 1309 void 1310 busdma_swi(void) 1311 { 1312 bus_dma_tag_t dmat; 1313 struct bus_dmamap *map; 1314 1315 mtx_lock(&bounce_lock); 1316 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1317 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1318 mtx_unlock(&bounce_lock); 1319 dmat = map->dmat; 1320 (dmat->common.lockfunc)(dmat->common.lockfuncarg, BUS_DMA_LOCK); 1321 bus_dmamap_load_mem(map->dmat, map, &map->mem, 1322 map->callback, map->callback_arg, BUS_DMA_WAITOK); 1323 (dmat->common.lockfunc)(dmat->common.lockfuncarg, 1324 BUS_DMA_UNLOCK); 1325 mtx_lock(&bounce_lock); 1326 } 1327 mtx_unlock(&bounce_lock); 1328 } 1329 1330 struct bus_dma_impl bus_dma_bounce_impl = { 1331 .tag_create = bounce_bus_dma_tag_create, 1332 .tag_destroy = bounce_bus_dma_tag_destroy, 1333 .tag_set_domain = bounce_bus_dma_tag_set_domain, 1334 .id_mapped = bounce_bus_dma_id_mapped, 1335 .map_create = bounce_bus_dmamap_create, 1336 .map_destroy = bounce_bus_dmamap_destroy, 1337 .mem_alloc = bounce_bus_dmamem_alloc, 1338 .mem_free = bounce_bus_dmamem_free, 1339 .load_phys = bounce_bus_dmamap_load_phys, 1340 .load_buffer = bounce_bus_dmamap_load_buffer, 1341 .load_ma = bounce_bus_dmamap_load_ma, 1342 .map_waitok = bounce_bus_dmamap_waitok, 1343 .map_complete = bounce_bus_dmamap_complete, 1344 .map_unload = bounce_bus_dmamap_unload, 1345 .map_sync = bounce_bus_dmamap_sync, 1346 }; 1347