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sys/amd64/amd64/busdma_machdep.c
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1 /*- 2 * Copyright (c) 1997, 1998 Justin T. Gibbs. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions, and the following disclaimer, 10 * without modification, immediately at the beginning of the file. 11 * 2. The name of the author may not be used to endorse or promote products 12 * derived from this software without specific prior written permission. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 18 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD: releng/8.1/sys/amd64/amd64/busdma_machdep.c 206610 2010-04-14 17:01:29Z gibbs $"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/malloc.h> 33 #include <sys/bus.h> 34 #include <sys/interrupt.h> 35 #include <sys/kernel.h> 36 #include <sys/ktr.h> 37 #include <sys/lock.h> 38 #include <sys/proc.h> 39 #include <sys/mutex.h> 40 #include <sys/mbuf.h> 41 #include <sys/uio.h> 42 #include <sys/sysctl.h> 43 44 #include <vm/vm.h> 45 #include <vm/vm_page.h> 46 #include <vm/vm_map.h> 47 48 #include <machine/atomic.h> 49 #include <machine/bus.h> 50 #include <machine/md_var.h> 51 #include <machine/specialreg.h> 52 53 #define MAX_BPAGES 8192 54 55 struct bounce_zone; 56 57 struct bus_dma_tag { 58 bus_dma_tag_t parent; 59 bus_size_t alignment; 60 bus_size_t boundary; 61 bus_addr_t lowaddr; 62 bus_addr_t highaddr; 63 bus_dma_filter_t *filter; 64 void *filterarg; 65 bus_size_t maxsize; 66 u_int nsegments; 67 bus_size_t maxsegsz; 68 int flags; 69 int ref_count; 70 int map_count; 71 bus_dma_lock_t *lockfunc; 72 void *lockfuncarg; 73 bus_dma_segment_t *segments; 74 struct bounce_zone *bounce_zone; 75 }; 76 77 struct bounce_page { 78 vm_offset_t vaddr; /* kva of bounce buffer */ 79 bus_addr_t busaddr; /* Physical address */ 80 vm_offset_t datavaddr; /* kva of client data */ 81 bus_size_t datacount; /* client data count */ 82 STAILQ_ENTRY(bounce_page) links; 83 }; 84 85 int busdma_swi_pending; 86 87 struct bounce_zone { 88 STAILQ_ENTRY(bounce_zone) links; 89 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 90 int total_bpages; 91 int free_bpages; 92 int reserved_bpages; 93 int active_bpages; 94 int total_bounced; 95 int total_deferred; 96 int map_count; 97 bus_size_t alignment; 98 bus_addr_t lowaddr; 99 char zoneid[8]; 100 char lowaddrid[20]; 101 struct sysctl_ctx_list sysctl_tree; 102 struct sysctl_oid *sysctl_tree_top; 103 }; 104 105 static struct mtx bounce_lock; 106 static int total_bpages; 107 static int busdma_zonecount; 108 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 109 110 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 111 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 112 "Total bounce pages"); 113 114 struct bus_dmamap { 115 struct bp_list bpages; 116 int pagesneeded; 117 int pagesreserved; 118 bus_dma_tag_t dmat; 119 void *buf; /* unmapped buffer pointer */ 120 bus_size_t buflen; /* unmapped buffer length */ 121 bus_dmamap_callback_t *callback; 122 void *callback_arg; 123 STAILQ_ENTRY(bus_dmamap) links; 124 }; 125 126 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 128 static struct bus_dmamap nobounce_dmamap; 129 130 static void init_bounce_pages(void *dummy); 131 static int alloc_bounce_zone(bus_dma_tag_t dmat); 132 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 133 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 134 int commit); 135 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 136 vm_offset_t vaddr, bus_size_t size); 137 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 138 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 139 140 /* 141 * Return true if a match is made. 142 * 143 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 144 * 145 * If paddr is within the bounds of the dma tag then call the filter callback 146 * to check for a match, if there is no filter callback then assume a match. 147 */ 148 static __inline int 149 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 150 { 151 int retval; 152 153 retval = 0; 154 155 do { 156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 157 || ((paddr & (dmat->alignment - 1)) != 0)) 158 && (dmat->filter == NULL 159 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 160 retval = 1; 161 162 dmat = dmat->parent; 163 } while (retval == 0 && dmat != NULL); 164 return (retval); 165 } 166 167 /* 168 * Convenience function for manipulating driver locks from busdma (during 169 * busdma_swi, for example). Drivers that don't provide their own locks 170 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 171 * non-mutex locking scheme don't have to use this at all. 172 */ 173 void 174 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 175 { 176 struct mtx *dmtx; 177 178 dmtx = (struct mtx *)arg; 179 switch (op) { 180 case BUS_DMA_LOCK: 181 mtx_lock(dmtx); 182 break; 183 case BUS_DMA_UNLOCK: 184 mtx_unlock(dmtx); 185 break; 186 default: 187 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 188 } 189 } 190 191 /* 192 * dflt_lock should never get called. It gets put into the dma tag when 193 * lockfunc == NULL, which is only valid if the maps that are associated 194 * with the tag are meant to never be defered. 195 * XXX Should have a way to identify which driver is responsible here. 196 */ 197 static void 198 dflt_lock(void *arg, bus_dma_lock_op_t op) 199 { 200 panic("driver error: busdma dflt_lock called"); 201 } 202 203 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 204 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 205 /* 206 * Allocate a device specific dma_tag. 207 */ 208 int 209 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 210 bus_size_t boundary, bus_addr_t lowaddr, 211 bus_addr_t highaddr, bus_dma_filter_t *filter, 212 void *filterarg, bus_size_t maxsize, int nsegments, 213 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 214 void *lockfuncarg, bus_dma_tag_t *dmat) 215 { 216 bus_dma_tag_t newtag; 217 int error = 0; 218 219 /* Basic sanity checking */ 220 if (boundary != 0 && boundary < maxsegsz) 221 maxsegsz = boundary; 222 223 if (maxsegsz == 0) { 224 return (EINVAL); 225 } 226 227 /* Return a NULL tag on failure */ 228 *dmat = NULL; 229 230 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 231 M_ZERO | M_NOWAIT); 232 if (newtag == NULL) { 233 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 234 __func__, newtag, 0, error); 235 return (ENOMEM); 236 } 237 238 newtag->parent = parent; 239 newtag->alignment = alignment; 240 newtag->boundary = boundary; 241 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 242 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 243 newtag->filter = filter; 244 newtag->filterarg = filterarg; 245 newtag->maxsize = maxsize; 246 newtag->nsegments = nsegments; 247 newtag->maxsegsz = maxsegsz; 248 newtag->flags = flags; 249 newtag->ref_count = 1; /* Count ourself */ 250 newtag->map_count = 0; 251 if (lockfunc != NULL) { 252 newtag->lockfunc = lockfunc; 253 newtag->lockfuncarg = lockfuncarg; 254 } else { 255 newtag->lockfunc = dflt_lock; 256 newtag->lockfuncarg = NULL; 257 } 258 newtag->segments = NULL; 259 260 /* Take into account any restrictions imposed by our parent tag */ 261 if (parent != NULL) { 262 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 263 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 264 if (newtag->boundary == 0) 265 newtag->boundary = parent->boundary; 266 else if (parent->boundary != 0) 267 newtag->boundary = MIN(parent->boundary, 268 newtag->boundary); 269 if (newtag->filter == NULL) { 270 /* 271 * Short circuit looking at our parent directly 272 * since we have encapsulated all of its information 273 */ 274 newtag->filter = parent->filter; 275 newtag->filterarg = parent->filterarg; 276 newtag->parent = parent->parent; 277 } 278 if (newtag->parent != NULL) 279 atomic_add_int(&parent->ref_count, 1); 280 } 281 282 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 283 || newtag->alignment > 1) 284 newtag->flags |= BUS_DMA_COULD_BOUNCE; 285 286 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 287 (flags & BUS_DMA_ALLOCNOW) != 0) { 288 struct bounce_zone *bz; 289 290 /* Must bounce */ 291 292 if ((error = alloc_bounce_zone(newtag)) != 0) { 293 free(newtag, M_DEVBUF); 294 return (error); 295 } 296 bz = newtag->bounce_zone; 297 298 if (ptoa(bz->total_bpages) < maxsize) { 299 int pages; 300 301 pages = atop(maxsize) - bz->total_bpages; 302 303 /* Add pages to our bounce pool */ 304 if (alloc_bounce_pages(newtag, pages) < pages) 305 error = ENOMEM; 306 } 307 /* Performed initial allocation */ 308 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 309 } 310 311 if (error != 0) { 312 free(newtag, M_DEVBUF); 313 } else { 314 *dmat = newtag; 315 } 316 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 317 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 318 return (error); 319 } 320 321 int 322 bus_dma_tag_destroy(bus_dma_tag_t dmat) 323 { 324 bus_dma_tag_t dmat_copy; 325 int error; 326 327 error = 0; 328 dmat_copy = dmat; 329 330 if (dmat != NULL) { 331 332 if (dmat->map_count != 0) { 333 error = EBUSY; 334 goto out; 335 } 336 337 while (dmat != NULL) { 338 bus_dma_tag_t parent; 339 340 parent = dmat->parent; 341 atomic_subtract_int(&dmat->ref_count, 1); 342 if (dmat->ref_count == 0) { 343 if (dmat->segments != NULL) 344 free(dmat->segments, M_DEVBUF); 345 free(dmat, M_DEVBUF); 346 /* 347 * Last reference count, so 348 * release our reference 349 * count on our parent. 350 */ 351 dmat = parent; 352 } else 353 dmat = NULL; 354 } 355 } 356 out: 357 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 358 return (error); 359 } 360 361 /* 362 * Allocate a handle for mapping from kva/uva/physical 363 * address space into bus device space. 364 */ 365 int 366 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 367 { 368 int error; 369 370 error = 0; 371 372 if (dmat->segments == NULL) { 373 dmat->segments = (bus_dma_segment_t *)malloc( 374 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 375 M_NOWAIT); 376 if (dmat->segments == NULL) { 377 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 378 __func__, dmat, ENOMEM); 379 return (ENOMEM); 380 } 381 } 382 383 /* 384 * Bouncing might be required if the driver asks for an active 385 * exclusion region, a data alignment that is stricter than 1, and/or 386 * an active address boundary. 387 */ 388 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 389 390 /* Must bounce */ 391 struct bounce_zone *bz; 392 int maxpages; 393 394 if (dmat->bounce_zone == NULL) { 395 if ((error = alloc_bounce_zone(dmat)) != 0) 396 return (error); 397 } 398 bz = dmat->bounce_zone; 399 400 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 401 M_NOWAIT | M_ZERO); 402 if (*mapp == NULL) { 403 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 404 __func__, dmat, ENOMEM); 405 return (ENOMEM); 406 } 407 408 /* Initialize the new map */ 409 STAILQ_INIT(&((*mapp)->bpages)); 410 411 /* 412 * Attempt to add pages to our pool on a per-instance 413 * basis up to a sane limit. 414 */ 415 if (dmat->alignment > 1) 416 maxpages = MAX_BPAGES; 417 else 418 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 419 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 420 || (bz->map_count > 0 && bz->total_bpages < maxpages)) { 421 int pages; 422 423 pages = MAX(atop(dmat->maxsize), 1); 424 pages = MIN(maxpages - bz->total_bpages, pages); 425 pages = MAX(pages, 1); 426 if (alloc_bounce_pages(dmat, pages) < pages) 427 error = ENOMEM; 428 429 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 430 if (error == 0) 431 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 432 } else { 433 error = 0; 434 } 435 } 436 bz->map_count++; 437 } else { 438 *mapp = NULL; 439 } 440 if (error == 0) 441 dmat->map_count++; 442 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 443 __func__, dmat, dmat->flags, error); 444 return (error); 445 } 446 447 /* 448 * Destroy a handle for mapping from kva/uva/physical 449 * address space into bus device space. 450 */ 451 int 452 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 453 { 454 if (map != NULL && map != &nobounce_dmamap) { 455 if (STAILQ_FIRST(&map->bpages) != NULL) { 456 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 457 __func__, dmat, EBUSY); 458 return (EBUSY); 459 } 460 if (dmat->bounce_zone) 461 dmat->bounce_zone->map_count--; 462 free(map, M_DEVBUF); 463 } 464 dmat->map_count--; 465 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 466 return (0); 467 } 468 469 470 /* 471 * Allocate a piece of memory that can be efficiently mapped into 472 * bus device space based on the constraints lited in the dma tag. 473 * A dmamap to for use with dmamap_load is also allocated. 474 */ 475 int 476 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 477 bus_dmamap_t *mapp) 478 { 479 int mflags; 480 481 if (flags & BUS_DMA_NOWAIT) 482 mflags = M_NOWAIT; 483 else 484 mflags = M_WAITOK; 485 486 /* If we succeed, no mapping/bouncing will be required */ 487 *mapp = NULL; 488 489 if (dmat->segments == NULL) { 490 dmat->segments = (bus_dma_segment_t *)malloc( 491 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 492 mflags); 493 if (dmat->segments == NULL) { 494 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 495 __func__, dmat, dmat->flags, ENOMEM); 496 return (ENOMEM); 497 } 498 } 499 if (flags & BUS_DMA_ZERO) 500 mflags |= M_ZERO; 501 502 /* 503 * XXX: 504 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 505 * alignment guarantees of malloc need to be nailed down, and the 506 * code below should be rewritten to take that into account. 507 * 508 * In the meantime, we'll warn the user if malloc gets it wrong. 509 */ 510 if ((dmat->maxsize <= PAGE_SIZE) && 511 (dmat->alignment < dmat->maxsize) && 512 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 513 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 514 } else { 515 /* 516 * XXX Use Contigmalloc until it is merged into this facility 517 * and handles multi-seg allocations. Nobody is doing 518 * multi-seg allocations yet though. 519 * XXX Certain AGP hardware does. 520 */ 521 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 522 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 523 dmat->boundary); 524 } 525 if (*vaddr == NULL) { 526 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 527 __func__, dmat, dmat->flags, ENOMEM); 528 return (ENOMEM); 529 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 530 printf("bus_dmamem_alloc failed to align memory properly.\n"); 531 } 532 if (flags & BUS_DMA_NOCACHE) 533 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 534 PAT_UNCACHEABLE); 535 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 536 __func__, dmat, dmat->flags, 0); 537 return (0); 538 } 539 540 /* 541 * Free a piece of memory and it's allociated dmamap, that was allocated 542 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 543 */ 544 void 545 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 546 { 547 /* 548 * dmamem does not need to be bounced, so the map should be 549 * NULL 550 */ 551 if (map != NULL) 552 panic("bus_dmamem_free: Invalid map freed\n"); 553 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 554 if ((dmat->maxsize <= PAGE_SIZE) && 555 (dmat->alignment < dmat->maxsize) && 556 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 557 free(vaddr, M_DEVBUF); 558 else { 559 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 560 } 561 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 562 } 563 564 /* 565 * Utility function to load a linear buffer. lastaddrp holds state 566 * between invocations (for multiple-buffer loads). segp contains 567 * the starting segment on entrace, and the ending segment on exit. 568 * first indicates if this is the first invocation of this function. 569 */ 570 static __inline int 571 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 572 bus_dmamap_t map, 573 void *buf, bus_size_t buflen, 574 pmap_t pmap, 575 int flags, 576 bus_addr_t *lastaddrp, 577 bus_dma_segment_t *segs, 578 int *segp, 579 int first) 580 { 581 bus_size_t sgsize; 582 bus_addr_t curaddr, lastaddr, baddr, bmask; 583 vm_offset_t vaddr; 584 bus_addr_t paddr; 585 int seg; 586 587 if (map == NULL) 588 map = &nobounce_dmamap; 589 590 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 591 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 592 vm_offset_t vendaddr; 593 594 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 595 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 596 dmat->boundary, dmat->alignment); 597 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 598 map, &nobounce_dmamap, map->pagesneeded); 599 /* 600 * Count the number of bounce pages 601 * needed in order to complete this transfer 602 */ 603 vaddr = (vm_offset_t)buf; 604 vendaddr = (vm_offset_t)buf + buflen; 605 606 while (vaddr < vendaddr) { 607 bus_size_t sg_len; 608 609 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 610 if (pmap) 611 paddr = pmap_extract(pmap, vaddr); 612 else 613 paddr = pmap_kextract(vaddr); 614 if (run_filter(dmat, paddr) != 0) { 615 sg_len = roundup2(sg_len, dmat->alignment); 616 map->pagesneeded++; 617 } 618 vaddr += sg_len; 619 } 620 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 621 } 622 623 /* Reserve Necessary Bounce Pages */ 624 if (map->pagesneeded != 0) { 625 mtx_lock(&bounce_lock); 626 if (flags & BUS_DMA_NOWAIT) { 627 if (reserve_bounce_pages(dmat, map, 0) != 0) { 628 mtx_unlock(&bounce_lock); 629 return (ENOMEM); 630 } 631 } else { 632 if (reserve_bounce_pages(dmat, map, 1) != 0) { 633 /* Queue us for resources */ 634 map->dmat = dmat; 635 map->buf = buf; 636 map->buflen = buflen; 637 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 638 map, links); 639 mtx_unlock(&bounce_lock); 640 return (EINPROGRESS); 641 } 642 } 643 mtx_unlock(&bounce_lock); 644 } 645 646 vaddr = (vm_offset_t)buf; 647 lastaddr = *lastaddrp; 648 bmask = ~(dmat->boundary - 1); 649 650 for (seg = *segp; buflen > 0 ; ) { 651 bus_size_t max_sgsize; 652 653 /* 654 * Get the physical address for this segment. 655 */ 656 if (pmap) 657 curaddr = pmap_extract(pmap, vaddr); 658 else 659 curaddr = pmap_kextract(vaddr); 660 661 /* 662 * Compute the segment size, and adjust counts. 663 */ 664 max_sgsize = MIN(buflen, dmat->maxsegsz); 665 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); 666 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 667 sgsize = roundup2(sgsize, dmat->alignment); 668 sgsize = MIN(sgsize, max_sgsize); 669 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 670 } else { 671 sgsize = MIN(sgsize, max_sgsize); 672 } 673 674 /* 675 * Make sure we don't cross any boundaries. 676 */ 677 if (dmat->boundary > 0) { 678 baddr = (curaddr + dmat->boundary) & bmask; 679 if (sgsize > (baddr - curaddr)) 680 sgsize = (baddr - curaddr); 681 } 682 683 /* 684 * Insert chunk into a segment, coalescing with 685 * previous segment if possible. 686 */ 687 if (first) { 688 segs[seg].ds_addr = curaddr; 689 segs[seg].ds_len = sgsize; 690 first = 0; 691 } else { 692 if (curaddr == lastaddr && 693 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 694 (dmat->boundary == 0 || 695 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 696 segs[seg].ds_len += sgsize; 697 else { 698 if (++seg >= dmat->nsegments) 699 break; 700 segs[seg].ds_addr = curaddr; 701 segs[seg].ds_len = sgsize; 702 } 703 } 704 705 lastaddr = curaddr + sgsize; 706 vaddr += sgsize; 707 buflen -= sgsize; 708 } 709 710 *segp = seg; 711 *lastaddrp = lastaddr; 712 713 /* 714 * Did we fit? 715 */ 716 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 717 } 718 719 /* 720 * Map the buffer buf into bus space using the dmamap map. 721 */ 722 int 723 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 724 bus_size_t buflen, bus_dmamap_callback_t *callback, 725 void *callback_arg, int flags) 726 { 727 bus_addr_t lastaddr = 0; 728 int error, nsegs = 0; 729 730 if (map != NULL) { 731 flags |= BUS_DMA_WAITOK; 732 map->callback = callback; 733 map->callback_arg = callback_arg; 734 } 735 736 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 737 &lastaddr, dmat->segments, &nsegs, 1); 738 739 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 740 __func__, dmat, dmat->flags, error, nsegs + 1); 741 742 if (error == EINPROGRESS) { 743 return (error); 744 } 745 746 if (error) 747 (*callback)(callback_arg, dmat->segments, 0, error); 748 else 749 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 750 751 /* 752 * Return ENOMEM to the caller so that it can pass it up the stack. 753 * This error only happens when NOWAIT is set, so deferal is disabled. 754 */ 755 if (error == ENOMEM) 756 return (error); 757 758 return (0); 759 } 760 761 762 /* 763 * Like _bus_dmamap_load(), but for mbufs. 764 */ 765 int 766 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 767 struct mbuf *m0, 768 bus_dmamap_callback2_t *callback, void *callback_arg, 769 int flags) 770 { 771 int nsegs, error; 772 773 M_ASSERTPKTHDR(m0); 774 775 flags |= BUS_DMA_NOWAIT; 776 nsegs = 0; 777 error = 0; 778 if (m0->m_pkthdr.len <= dmat->maxsize) { 779 int first = 1; 780 bus_addr_t lastaddr = 0; 781 struct mbuf *m; 782 783 for (m = m0; m != NULL && error == 0; m = m->m_next) { 784 if (m->m_len > 0) { 785 error = _bus_dmamap_load_buffer(dmat, map, 786 m->m_data, m->m_len, 787 NULL, flags, &lastaddr, 788 dmat->segments, &nsegs, first); 789 first = 0; 790 } 791 } 792 } else { 793 error = EINVAL; 794 } 795 796 if (error) { 797 /* force "no valid mappings" in callback */ 798 (*callback)(callback_arg, dmat->segments, 0, 0, error); 799 } else { 800 (*callback)(callback_arg, dmat->segments, 801 nsegs+1, m0->m_pkthdr.len, error); 802 } 803 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 804 __func__, dmat, dmat->flags, error, nsegs + 1); 805 return (error); 806 } 807 808 int 809 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 810 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 811 int flags) 812 { 813 int error; 814 815 M_ASSERTPKTHDR(m0); 816 817 flags |= BUS_DMA_NOWAIT; 818 *nsegs = 0; 819 error = 0; 820 if (m0->m_pkthdr.len <= dmat->maxsize) { 821 int first = 1; 822 bus_addr_t lastaddr = 0; 823 struct mbuf *m; 824 825 for (m = m0; m != NULL && error == 0; m = m->m_next) { 826 if (m->m_len > 0) { 827 error = _bus_dmamap_load_buffer(dmat, map, 828 m->m_data, m->m_len, 829 NULL, flags, &lastaddr, 830 segs, nsegs, first); 831 first = 0; 832 } 833 } 834 } else { 835 error = EINVAL; 836 } 837 838 /* XXX FIXME: Having to increment nsegs is really annoying */ 839 ++*nsegs; 840 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 841 __func__, dmat, dmat->flags, error, *nsegs); 842 return (error); 843 } 844 845 /* 846 * Like _bus_dmamap_load(), but for uios. 847 */ 848 int 849 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 850 struct uio *uio, 851 bus_dmamap_callback2_t *callback, void *callback_arg, 852 int flags) 853 { 854 bus_addr_t lastaddr = 0; 855 int nsegs, error, first, i; 856 bus_size_t resid; 857 struct iovec *iov; 858 pmap_t pmap; 859 860 flags |= BUS_DMA_NOWAIT; 861 resid = uio->uio_resid; 862 iov = uio->uio_iov; 863 864 if (uio->uio_segflg == UIO_USERSPACE) { 865 KASSERT(uio->uio_td != NULL, 866 ("bus_dmamap_load_uio: USERSPACE but no proc")); 867 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 868 } else 869 pmap = NULL; 870 871 nsegs = 0; 872 error = 0; 873 first = 1; 874 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 875 /* 876 * Now at the first iovec to load. Load each iovec 877 * until we have exhausted the residual count. 878 */ 879 bus_size_t minlen = 880 resid < iov[i].iov_len ? resid : iov[i].iov_len; 881 caddr_t addr = (caddr_t) iov[i].iov_base; 882 883 if (minlen > 0) { 884 error = _bus_dmamap_load_buffer(dmat, map, 885 addr, minlen, pmap, flags, &lastaddr, 886 dmat->segments, &nsegs, first); 887 first = 0; 888 889 resid -= minlen; 890 } 891 } 892 893 if (error) { 894 /* force "no valid mappings" in callback */ 895 (*callback)(callback_arg, dmat->segments, 0, 0, error); 896 } else { 897 (*callback)(callback_arg, dmat->segments, 898 nsegs+1, uio->uio_resid, error); 899 } 900 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 901 __func__, dmat, dmat->flags, error, nsegs + 1); 902 return (error); 903 } 904 905 /* 906 * Release the mapping held by map. 907 */ 908 void 909 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 910 { 911 struct bounce_page *bpage; 912 913 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 914 STAILQ_REMOVE_HEAD(&map->bpages, links); 915 free_bounce_page(dmat, bpage); 916 } 917 } 918 919 void 920 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 921 { 922 struct bounce_page *bpage; 923 924 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 925 /* 926 * Handle data bouncing. We might also 927 * want to add support for invalidating 928 * the caches on broken hardware 929 */ 930 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 931 "performing bounce", __func__, op, dmat, dmat->flags); 932 933 if (op & BUS_DMASYNC_PREWRITE) { 934 while (bpage != NULL) { 935 bcopy((void *)bpage->datavaddr, 936 (void *)bpage->vaddr, 937 bpage->datacount); 938 bpage = STAILQ_NEXT(bpage, links); 939 } 940 dmat->bounce_zone->total_bounced++; 941 } 942 943 if (op & BUS_DMASYNC_POSTREAD) { 944 while (bpage != NULL) { 945 bcopy((void *)bpage->vaddr, 946 (void *)bpage->datavaddr, 947 bpage->datacount); 948 bpage = STAILQ_NEXT(bpage, links); 949 } 950 dmat->bounce_zone->total_bounced++; 951 } 952 } 953 } 954 955 static void 956 init_bounce_pages(void *dummy __unused) 957 { 958 959 total_bpages = 0; 960 STAILQ_INIT(&bounce_zone_list); 961 STAILQ_INIT(&bounce_map_waitinglist); 962 STAILQ_INIT(&bounce_map_callbacklist); 963 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 964 } 965 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 966 967 static struct sysctl_ctx_list * 968 busdma_sysctl_tree(struct bounce_zone *bz) 969 { 970 return (&bz->sysctl_tree); 971 } 972 973 static struct sysctl_oid * 974 busdma_sysctl_tree_top(struct bounce_zone *bz) 975 { 976 return (bz->sysctl_tree_top); 977 } 978 979 static int 980 alloc_bounce_zone(bus_dma_tag_t dmat) 981 { 982 struct bounce_zone *bz; 983 984 /* Check to see if we already have a suitable zone */ 985 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 986 if ((dmat->alignment <= bz->alignment) 987 && (dmat->lowaddr >= bz->lowaddr)) { 988 dmat->bounce_zone = bz; 989 return (0); 990 } 991 } 992 993 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 994 M_NOWAIT | M_ZERO)) == NULL) 995 return (ENOMEM); 996 997 STAILQ_INIT(&bz->bounce_page_list); 998 bz->free_bpages = 0; 999 bz->reserved_bpages = 0; 1000 bz->active_bpages = 0; 1001 bz->lowaddr = dmat->lowaddr; 1002 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 1003 bz->map_count = 0; 1004 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1005 busdma_zonecount++; 1006 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1007 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1008 dmat->bounce_zone = bz; 1009 1010 sysctl_ctx_init(&bz->sysctl_tree); 1011 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1012 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1013 CTLFLAG_RD, 0, ""); 1014 if (bz->sysctl_tree_top == NULL) { 1015 sysctl_ctx_free(&bz->sysctl_tree); 1016 return (0); /* XXX error code? */ 1017 } 1018 1019 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1020 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1021 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1022 "Total bounce pages"); 1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1025 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1026 "Free bounce pages"); 1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1029 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1030 "Reserved bounce pages"); 1031 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1032 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1033 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1034 "Active bounce pages"); 1035 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1036 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1037 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1038 "Total bounce requests"); 1039 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1040 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1041 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1042 "Total bounce requests that were deferred"); 1043 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1045 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1046 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1047 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1048 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1049 1050 return (0); 1051 } 1052 1053 static int 1054 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1055 { 1056 struct bounce_zone *bz; 1057 int count; 1058 1059 bz = dmat->bounce_zone; 1060 count = 0; 1061 while (numpages > 0) { 1062 struct bounce_page *bpage; 1063 1064 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1065 M_NOWAIT | M_ZERO); 1066 1067 if (bpage == NULL) 1068 break; 1069 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1070 M_NOWAIT, 0ul, 1071 bz->lowaddr, 1072 PAGE_SIZE, 1073 0); 1074 if (bpage->vaddr == 0) { 1075 free(bpage, M_DEVBUF); 1076 break; 1077 } 1078 bpage->busaddr = pmap_kextract(bpage->vaddr); 1079 mtx_lock(&bounce_lock); 1080 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1081 total_bpages++; 1082 bz->total_bpages++; 1083 bz->free_bpages++; 1084 mtx_unlock(&bounce_lock); 1085 count++; 1086 numpages--; 1087 } 1088 return (count); 1089 } 1090 1091 static int 1092 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1093 { 1094 struct bounce_zone *bz; 1095 int pages; 1096 1097 mtx_assert(&bounce_lock, MA_OWNED); 1098 bz = dmat->bounce_zone; 1099 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1100 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1101 return (map->pagesneeded - (map->pagesreserved + pages)); 1102 bz->free_bpages -= pages; 1103 bz->reserved_bpages += pages; 1104 map->pagesreserved += pages; 1105 pages = map->pagesneeded - map->pagesreserved; 1106 1107 return (pages); 1108 } 1109 1110 static bus_addr_t 1111 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1112 bus_size_t size) 1113 { 1114 struct bounce_zone *bz; 1115 struct bounce_page *bpage; 1116 1117 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1118 KASSERT(map != NULL && map != &nobounce_dmamap, 1119 ("add_bounce_page: bad map %p", map)); 1120 1121 bz = dmat->bounce_zone; 1122 if (map->pagesneeded == 0) 1123 panic("add_bounce_page: map doesn't need any pages"); 1124 map->pagesneeded--; 1125 1126 if (map->pagesreserved == 0) 1127 panic("add_bounce_page: map doesn't need any pages"); 1128 map->pagesreserved--; 1129 1130 mtx_lock(&bounce_lock); 1131 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1132 if (bpage == NULL) 1133 panic("add_bounce_page: free page list is empty"); 1134 1135 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1136 bz->reserved_bpages--; 1137 bz->active_bpages++; 1138 mtx_unlock(&bounce_lock); 1139 1140 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1141 /* Page offset needs to be preserved. */ 1142 bpage->vaddr |= vaddr & PAGE_MASK; 1143 bpage->busaddr |= vaddr & PAGE_MASK; 1144 } 1145 bpage->datavaddr = vaddr; 1146 bpage->datacount = size; 1147 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1148 return (bpage->busaddr); 1149 } 1150 1151 static void 1152 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1153 { 1154 struct bus_dmamap *map; 1155 struct bounce_zone *bz; 1156 1157 bz = dmat->bounce_zone; 1158 bpage->datavaddr = 0; 1159 bpage->datacount = 0; 1160 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1161 /* 1162 * Reset the bounce page to start at offset 0. Other uses 1163 * of this bounce page may need to store a full page of 1164 * data and/or assume it starts on a page boundary. 1165 */ 1166 bpage->vaddr &= ~PAGE_MASK; 1167 bpage->busaddr &= ~PAGE_MASK; 1168 } 1169 1170 mtx_lock(&bounce_lock); 1171 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1172 bz->free_bpages++; 1173 bz->active_bpages--; 1174 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1175 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1176 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1177 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1178 map, links); 1179 busdma_swi_pending = 1; 1180 bz->total_deferred++; 1181 swi_sched(vm_ih, 0); 1182 } 1183 } 1184 mtx_unlock(&bounce_lock); 1185 } 1186 1187 void 1188 busdma_swi(void) 1189 { 1190 bus_dma_tag_t dmat; 1191 struct bus_dmamap *map; 1192 1193 mtx_lock(&bounce_lock); 1194 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1195 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1196 mtx_unlock(&bounce_lock); 1197 dmat = map->dmat; 1198 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1199 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1200 map->callback, map->callback_arg, /*flags*/0); 1201 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1202 mtx_lock(&bounce_lock); 1203 } 1204 mtx_unlock(&bounce_lock); 1205 }
Cache object: 09f1d23cf403ba09b01284e50a52363f
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