busdma_machdep.c revision 158264
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: head/sys/i386/i386/busdma_machdep.c 158264 2006-05-03 04:14:17Z scottl $"); 29 30#include <sys/param.h> 31#include <sys/kdb.h> 32#include <ddb/ddb.h> 33#include <ddb/db_output.h> 34#include <sys/systm.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/mutex.h> 43#include <sys/mbuf.h> 44#include <sys/uio.h> 45#include <sys/sysctl.h> 46 47#include <vm/vm.h> 48#include <vm/vm_page.h> 49#include <vm/vm_map.h> 50 51#include <machine/atomic.h> 52#include <machine/bus.h> 53#include <machine/md_var.h> 54 55#define MAX_BPAGES 512 56 57struct bounce_zone; 58 59struct bus_dma_tag { 60 bus_dma_tag_t parent; 61 bus_size_t alignment; 62 bus_size_t boundary; 63 bus_addr_t lowaddr; 64 bus_addr_t highaddr; 65 bus_dma_filter_t *filter; 66 void *filterarg; 67 bus_size_t maxsize; 68 u_int nsegments; 69 bus_size_t maxsegsz; 70 int flags; 71 int ref_count; 72 int map_count; 73 bus_dma_lock_t *lockfunc; 74 void *lockfuncarg; 75 bus_dma_segment_t *segments; 76 struct bounce_zone *bounce_zone; 77}; 78 79struct bounce_page { 80 vm_offset_t vaddr; /* kva of bounce buffer */ 81 bus_addr_t busaddr; /* Physical address */ 82 vm_offset_t datavaddr; /* kva of client data */ 83 bus_size_t datacount; /* client data count */ 84 STAILQ_ENTRY(bounce_page) links; 85}; 86 87int busdma_swi_pending; 88 89struct bounce_zone { 90 STAILQ_ENTRY(bounce_zone) links; 91 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 92 int total_bpages; 93 int free_bpages; 94 int reserved_bpages; 95 int active_bpages; 96 int total_bounced; 97 int total_deferred; 98 bus_size_t alignment; 99 bus_size_t boundary; 100 bus_addr_t lowaddr; 101 char zoneid[8]; 102 char lowaddrid[20]; 103 struct sysctl_ctx_list sysctl_tree; 104 struct sysctl_oid *sysctl_tree_top; 105}; 106 107static struct mtx bounce_lock; 108static int total_bpages; 109static int busdma_zonecount; 110static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 111 112SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 113SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 114 "Total bounce pages"); 115 116struct bus_dmamap { 117 struct bp_list bpages; 118 int pagesneeded; 119 int pagesreserved; 120 bus_dma_tag_t dmat; 121 void *buf; /* unmapped buffer pointer */ 122 bus_size_t buflen; /* unmapped buffer length */ 123 bus_dmamap_callback_t *callback; 124 void *callback_arg; 125 STAILQ_ENTRY(bus_dmamap) links; 126}; 127 128static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 129static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 130static struct bus_dmamap nobounce_dmamap; 131 132static void init_bounce_pages(void *dummy); 133static int alloc_bounce_zone(bus_dma_tag_t dmat); 134static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 135static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 136 int commit); 137static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 138 vm_offset_t vaddr, bus_size_t size); 139static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 140static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 141 142/* 143 * Return true if a match is made. 144 * 145 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 146 * 147 * If paddr is within the bounds of the dma tag then call the filter callback 148 * to check for a match, if there is no filter callback then assume a match. 149 */ 150static __inline int 151run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 152{ 153 int retval; 154 155 retval = 0; 156 157 do { 158 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 159 || ((paddr & (dmat->alignment - 1)) != 0)) 160 && (dmat->filter == NULL 161 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 162 retval = 1; 163 164 dmat = dmat->parent; 165 } while (retval == 0 && dmat != NULL); 166 return (retval); 167} 168 169/* 170 * Convenience function for manipulating driver locks from busdma (during 171 * busdma_swi, for example). Drivers that don't provide their own locks 172 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 173 * non-mutex locking scheme don't have to use this at all. 174 */ 175void 176busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 177{ 178 struct mtx *dmtx; 179 180 dmtx = (struct mtx *)arg; 181 switch (op) { 182 case BUS_DMA_LOCK: 183 mtx_lock(dmtx); 184 break; 185 case BUS_DMA_UNLOCK: 186 mtx_unlock(dmtx); 187 break; 188 default: 189 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 190 } 191} 192 193/* 194 * dflt_lock should never get called. It gets put into the dma tag when 195 * lockfunc == NULL, which is only valid if the maps that are associated 196 * with the tag are meant to never be defered. 197 * XXX Should have a way to identify which driver is responsible here. 198 */ 199static void 200dflt_lock(void *arg, bus_dma_lock_op_t op) 201{ 202 panic("driver error: busdma dflt_lock called"); 203} 204 205#define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 206#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 207/* 208 * Allocate a device specific dma_tag. 209 */ 210int 211bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 212 bus_size_t boundary, bus_addr_t lowaddr, 213 bus_addr_t highaddr, bus_dma_filter_t *filter, 214 void *filterarg, bus_size_t maxsize, int nsegments, 215 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 216 void *lockfuncarg, bus_dma_tag_t *dmat) 217{ 218 bus_dma_tag_t newtag; 219 int error = 0; 220 221 /* Basic sanity checking */ 222 if (boundary != 0 && boundary < maxsegsz) 223 maxsegsz = boundary; 224 225 /* Return a NULL tag on failure */ 226 *dmat = NULL; 227 228 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 229 M_ZERO | M_NOWAIT); 230 if (newtag == NULL) { 231 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 232 __func__, newtag, 0, error); 233 return (ENOMEM); 234 } 235 236 newtag->parent = parent; 237 newtag->alignment = alignment; 238 newtag->boundary = boundary; 239 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 240 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 241 (PAGE_SIZE - 1); 242 newtag->filter = filter; 243 newtag->filterarg = filterarg; 244 newtag->maxsize = maxsize; 245 newtag->nsegments = nsegments; 246 newtag->maxsegsz = maxsegsz; 247 newtag->flags = flags; 248 newtag->ref_count = 1; /* Count ourself */ 249 newtag->map_count = 0; 250 if (lockfunc != NULL) { 251 newtag->lockfunc = lockfunc; 252 newtag->lockfuncarg = lockfuncarg; 253 } else { 254 newtag->lockfunc = dflt_lock; 255 newtag->lockfuncarg = NULL; 256 } 257 newtag->segments = NULL; 258 259 /* Take into account any restrictions imposed by our parent tag */ 260 if (parent != NULL) { 261 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 262 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 263 if (newtag->boundary == 0) 264 newtag->boundary = parent->boundary; 265 else if (parent->boundary != 0) 266 newtag->boundary = MIN(parent->boundary, 267 newtag->boundary); 268 if (newtag->filter == NULL) { 269 /* 270 * Short circuit looking at our parent directly 271 * since we have encapsulated all of its information 272 */ 273 newtag->filter = parent->filter; 274 newtag->filterarg = parent->filterarg; 275 newtag->parent = parent->parent; 276 } 277 if (newtag->parent != NULL) 278 atomic_add_int(&parent->ref_count, 1); 279 } 280 281 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 282 || newtag->alignment > 1) 283 newtag->flags |= BUS_DMA_COULD_BOUNCE; 284 285 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 286 (flags & BUS_DMA_ALLOCNOW) != 0) { 287 struct bounce_zone *bz; 288 289 /* Must bounce */ 290 291 if ((error = alloc_bounce_zone(newtag)) != 0) { 292 free(newtag, M_DEVBUF); 293 return (error); 294 } 295 bz = newtag->bounce_zone; 296 297 if (ptoa(bz->total_bpages) < maxsize) { 298 int pages; 299 300 pages = atop(maxsize) - bz->total_bpages; 301 302 /* Add pages to our bounce pool */ 303 if (alloc_bounce_pages(newtag, pages) < pages) 304 error = ENOMEM; 305 } 306 /* Performed initial allocation */ 307 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 308 } 309 310 if (error != 0) { 311 free(newtag, M_DEVBUF); 312 } else { 313 *dmat = newtag; 314 } 315 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 316 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 317 return (error); 318} 319 320int 321bus_dma_tag_destroy(bus_dma_tag_t dmat) 322{ 323 bus_dma_tag_t dmat_copy; 324 int error; 325 326 error = 0; 327 dmat_copy = dmat; 328 329 if (dmat != NULL) { 330 331 if (dmat->map_count != 0) { 332 error = EBUSY; 333 goto out; 334 } 335 336 while (dmat != NULL) { 337 bus_dma_tag_t parent; 338 339 parent = dmat->parent; 340 atomic_subtract_int(&dmat->ref_count, 1); 341 if (dmat->ref_count == 0) { 342 if (dmat->segments != NULL) 343 free(dmat->segments, M_DEVBUF); 344 free(dmat, M_DEVBUF); 345 /* 346 * Last reference count, so 347 * release our reference 348 * count on our parent. 349 */ 350 dmat = parent; 351 } else 352 dmat = NULL; 353 } 354 } 355out: 356 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 357 return (error); 358} 359 360/* 361 * Allocate a handle for mapping from kva/uva/physical 362 * address space into bus device space. 363 */ 364int 365bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 366{ 367 int error; 368 369 error = 0; 370 371 if (dmat->segments == NULL) { 372 dmat->segments = (bus_dma_segment_t *)malloc( 373 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 374 M_NOWAIT); 375 if (dmat->segments == NULL) { 376 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 377 __func__, dmat, ENOMEM); 378 return (ENOMEM); 379 } 380 } 381 382 /* 383 * Bouncing might be required if the driver asks for an active 384 * exclusion region, a data alignment that is stricter than 1, and/or 385 * an active address boundary. 386 */ 387 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 388 389 /* Must bounce */ 390 struct bounce_zone *bz; 391 int maxpages; 392 393 if (dmat->bounce_zone == NULL) { 394 if ((error = alloc_bounce_zone(dmat)) != 0) 395 return (error); 396 } 397 bz = dmat->bounce_zone; 398 399 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 400 M_NOWAIT | M_ZERO); 401 if (*mapp == NULL) { 402 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 403 __func__, dmat, ENOMEM); 404 return (ENOMEM); 405 } 406 407 /* Initialize the new map */ 408 STAILQ_INIT(&((*mapp)->bpages)); 409 410 /* 411 * Attempt to add pages to our pool on a per-instance 412 * basis up to a sane limit. 413 */ 414 if (dmat->alignment > 1) 415 maxpages = MAX_BPAGES; 416 else 417 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 418 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 419 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 420 int pages; 421 422 pages = MAX(atop(dmat->maxsize), 1); 423 pages = MIN(maxpages - bz->total_bpages, pages); 424 pages = MAX(pages, 1); 425 if (alloc_bounce_pages(dmat, pages) < pages) 426 error = ENOMEM; 427 428 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 429 if (error == 0) 430 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 431 } else { 432 error = 0; 433 } 434 } 435 } else { 436 *mapp = NULL; 437 } 438 if (error == 0) 439 dmat->map_count++; 440 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 441 __func__, dmat, dmat->flags, error); 442 return (error); 443} 444 445/* 446 * Destroy a handle for mapping from kva/uva/physical 447 * address space into bus device space. 448 */ 449int 450bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 451{ 452 if (map != NULL && map != &nobounce_dmamap) { 453 if (STAILQ_FIRST(&map->bpages) != NULL) { 454 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 455 __func__, dmat, EBUSY); 456 return (EBUSY); 457 } 458 free(map, M_DEVBUF); 459 } 460 dmat->map_count--; 461 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 462 return (0); 463} 464 465 466/* 467 * Allocate a piece of memory that can be efficiently mapped into 468 * bus device space based on the constraints lited in the dma tag. 469 * A dmamap to for use with dmamap_load is also allocated. 470 */ 471int 472bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 473 bus_dmamap_t *mapp) 474{ 475 int mflags; 476 477 if (flags & BUS_DMA_NOWAIT) 478 mflags = M_NOWAIT; 479 else 480 mflags = M_WAITOK; 481 if (flags & BUS_DMA_ZERO) 482 mflags |= M_ZERO; 483 484 /* If we succeed, no mapping/bouncing will be required */ 485 *mapp = NULL; 486 487 if (dmat->segments == NULL) { 488 dmat->segments = (bus_dma_segment_t *)malloc( 489 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 490 M_NOWAIT); 491 if (dmat->segments == NULL) { 492 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 493 __func__, dmat, dmat->flags, ENOMEM); 494 return (ENOMEM); 495 } 496 } 497 498 if ((dmat->maxsize <= PAGE_SIZE) && 499 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 500 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 501 } else { 502 /* 503 * XXX Use Contigmalloc until it is merged into this facility 504 * and handles multi-seg allocations. Nobody is doing 505 * multi-seg allocations yet though. 506 * XXX Certain AGP hardware does. 507 */ 508 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 509 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 510 dmat->boundary); 511 } 512 if (*vaddr == NULL) { 513 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 514 __func__, dmat, dmat->flags, ENOMEM); 515 return (ENOMEM); 516 } 517 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 518 __func__, dmat, dmat->flags, ENOMEM); 519 return (0); 520} 521 522/* 523 * Free a piece of memory and it's allociated dmamap, that was allocated 524 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 525 */ 526void 527bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 528{ 529 /* 530 * dmamem does not need to be bounced, so the map should be 531 * NULL 532 */ 533 if (map != NULL) 534 panic("bus_dmamem_free: Invalid map freed\n"); 535 if ((dmat->maxsize <= PAGE_SIZE) 536 && dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 537 free(vaddr, M_DEVBUF); 538 else { 539 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 540 } 541 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 542} 543 544/* 545 * Utility function to load a linear buffer. lastaddrp holds state 546 * between invocations (for multiple-buffer loads). segp contains 547 * the starting segment on entrace, and the ending segment on exit. 548 * first indicates if this is the first invocation of this function. 549 */ 550static __inline int 551_bus_dmamap_load_buffer(bus_dma_tag_t dmat, 552 bus_dmamap_t map, 553 void *buf, bus_size_t buflen, 554 pmap_t pmap, 555 int flags, 556 bus_addr_t *lastaddrp, 557 bus_dma_segment_t *segs, 558 int *segp, 559 int first) 560{ 561 bus_size_t sgsize; 562 bus_addr_t curaddr, lastaddr, baddr, bmask; 563 vm_offset_t vaddr; 564 bus_addr_t paddr; 565 int needbounce = 0; 566 int seg; 567 568 if (map == NULL) 569 map = &nobounce_dmamap; 570 571 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 572 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 573 vm_offset_t vendaddr; 574 575 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 576 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 577 dmat->boundary, dmat->alignment); 578 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 579 map, &nobounce_dmamap, map->pagesneeded); 580 /* 581 * Count the number of bounce pages 582 * needed in order to complete this transfer 583 */ 584 vaddr = trunc_page((vm_offset_t)buf); 585 vendaddr = (vm_offset_t)buf + buflen; 586 587 while (vaddr < vendaddr) { 588 paddr = pmap_kextract(vaddr); 589 if (run_filter(dmat, paddr) != 0) { 590 needbounce = 1; 591 map->pagesneeded++; 592 } 593 vaddr += PAGE_SIZE; 594 } 595 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 596 } 597 598 /* Reserve Necessary Bounce Pages */ 599 if (map->pagesneeded != 0) { 600 mtx_lock(&bounce_lock); 601 if (flags & BUS_DMA_NOWAIT) { 602 if (reserve_bounce_pages(dmat, map, 0) != 0) { 603 mtx_unlock(&bounce_lock); 604 return (ENOMEM); 605 } 606 } else { 607 if (reserve_bounce_pages(dmat, map, 1) != 0) { 608 /* Queue us for resources */ 609 map->dmat = dmat; 610 map->buf = buf; 611 map->buflen = buflen; 612 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 613 map, links); 614 mtx_unlock(&bounce_lock); 615 return (EINPROGRESS); 616 } 617 } 618 mtx_unlock(&bounce_lock); 619 } 620 621 vaddr = (vm_offset_t)buf; 622 lastaddr = *lastaddrp; 623 bmask = ~(dmat->boundary - 1); 624 625 for (seg = *segp; buflen > 0 ; ) { 626 /* 627 * Get the physical address for this segment. 628 */ 629 if (pmap) 630 curaddr = pmap_extract(pmap, vaddr); 631 else 632 curaddr = pmap_kextract(vaddr); 633 634 /* 635 * Compute the segment size, and adjust counts. 636 */ 637 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 638 if (buflen < sgsize) 639 sgsize = buflen; 640 641 /* 642 * Make sure we don't cross any boundaries. 643 */ 644 if (dmat->boundary > 0) { 645 baddr = (curaddr + dmat->boundary) & bmask; 646 if (sgsize > (baddr - curaddr)) 647 sgsize = (baddr - curaddr); 648 } 649 650 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) 651 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 652 653 /* 654 * Insert chunk into a segment, coalescing with 655 * previous segment if possible. 656 */ 657 if (first) { 658 segs[seg].ds_addr = curaddr; 659 segs[seg].ds_len = sgsize; 660 first = 0; 661 } else { 662 if (needbounce == 0 && curaddr == lastaddr && 663 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 664 (dmat->boundary == 0 || 665 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 666 segs[seg].ds_len += sgsize; 667 else { 668 if (++seg >= dmat->nsegments) 669 break; 670 segs[seg].ds_addr = curaddr; 671 segs[seg].ds_len = sgsize; 672 } 673 } 674 675 lastaddr = curaddr + sgsize; 676 vaddr += sgsize; 677 buflen -= sgsize; 678 } 679 680 *segp = seg; 681 *lastaddrp = lastaddr; 682 683 /* 684 * Did we fit? 685 */ 686 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 687} 688 689/* 690 * Map the buffer buf into bus space using the dmamap map. 691 */ 692int 693bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 694 bus_size_t buflen, bus_dmamap_callback_t *callback, 695 void *callback_arg, int flags) 696{ 697 bus_addr_t lastaddr = 0; 698 int error, nsegs = 0; 699 700 if (map != NULL) { 701 flags |= BUS_DMA_WAITOK; 702 map->callback = callback; 703 map->callback_arg = callback_arg; 704 } 705 706 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 707 &lastaddr, dmat->segments, &nsegs, 1); 708 709 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 710 __func__, dmat, dmat->flags, error, nsegs + 1); 711 712 if (error == EINPROGRESS) { 713 return (error); 714 } 715 716 if (error) 717 (*callback)(callback_arg, dmat->segments, 0, error); 718 else 719 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 720 721 /* 722 * Return ENOMEM to the caller so that it can pass it up the stack. 723 * This error only happens when NOWAIT is set, so deferal is disabled. 724 */ 725 if (error == ENOMEM) 726 return (error); 727 728 return (0); 729} 730 731 732/* 733 * Like _bus_dmamap_load(), but for mbufs. 734 */ 735int 736bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 737 struct mbuf *m0, 738 bus_dmamap_callback2_t *callback, void *callback_arg, 739 int flags) 740{ 741 int nsegs, error; 742 743 M_ASSERTPKTHDR(m0); 744 745 flags |= BUS_DMA_NOWAIT; 746 nsegs = 0; 747 error = 0; 748 if (m0->m_pkthdr.len <= dmat->maxsize) { 749 int first = 1; 750 bus_addr_t lastaddr = 0; 751 struct mbuf *m; 752 753 for (m = m0; m != NULL && error == 0; m = m->m_next) { 754 if (m->m_len > 0) { 755 error = _bus_dmamap_load_buffer(dmat, map, 756 m->m_data, m->m_len, 757 NULL, flags, &lastaddr, 758 dmat->segments, &nsegs, first); 759 first = 0; 760 } 761 } 762 } else { 763 error = EINVAL; 764 } 765 766 if (error) { 767 /* force "no valid mappings" in callback */ 768 (*callback)(callback_arg, dmat->segments, 0, 0, error); 769 } else { 770 (*callback)(callback_arg, dmat->segments, 771 nsegs+1, m0->m_pkthdr.len, error); 772 } 773 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 774 __func__, dmat, dmat->flags, error, nsegs + 1); 775 return (error); 776} 777 778int 779bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 780 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 781 int flags) 782{ 783 int error; 784 785 M_ASSERTPKTHDR(m0); 786 787 flags |= BUS_DMA_NOWAIT; 788 *nsegs = 0; 789 error = 0; 790 if (m0->m_pkthdr.len <= dmat->maxsize) { 791 int first = 1; 792 bus_addr_t lastaddr = 0; 793 struct mbuf *m; 794 795 for (m = m0; m != NULL && error == 0; m = m->m_next) { 796 if (m->m_len > 0) { 797 error = _bus_dmamap_load_buffer(dmat, map, 798 m->m_data, m->m_len, 799 NULL, flags, &lastaddr, 800 segs, nsegs, first); 801 first = 0; 802 } 803 } 804 } else { 805 error = EINVAL; 806 } 807 808 /* XXX FIXME: Having to increment nsegs is really annoying */ 809 ++*nsegs; 810 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 811 __func__, dmat, dmat->flags, error, *nsegs); 812 return (error); 813} 814 815/* 816 * Like _bus_dmamap_load(), but for uios. 817 */ 818int 819bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 820 struct uio *uio, 821 bus_dmamap_callback2_t *callback, void *callback_arg, 822 int flags) 823{ 824 bus_addr_t lastaddr; 825 int nsegs, error, first, i; 826 bus_size_t resid; 827 struct iovec *iov; 828 pmap_t pmap; 829 830 flags |= BUS_DMA_NOWAIT; 831 resid = uio->uio_resid; 832 iov = uio->uio_iov; 833 834 if (uio->uio_segflg == UIO_USERSPACE) { 835 KASSERT(uio->uio_td != NULL, 836 ("bus_dmamap_load_uio: USERSPACE but no proc")); 837 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 838 } else 839 pmap = NULL; 840 841 nsegs = 0; 842 error = 0; 843 first = 1; 844 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 845 /* 846 * Now at the first iovec to load. Load each iovec 847 * until we have exhausted the residual count. 848 */ 849 bus_size_t minlen = 850 resid < iov[i].iov_len ? resid : iov[i].iov_len; 851 caddr_t addr = (caddr_t) iov[i].iov_base; 852 853 if (minlen > 0) { 854 error = _bus_dmamap_load_buffer(dmat, map, 855 addr, minlen, pmap, flags, &lastaddr, 856 dmat->segments, &nsegs, first); 857 first = 0; 858 859 resid -= minlen; 860 } 861 } 862 863 if (error) { 864 /* force "no valid mappings" in callback */ 865 (*callback)(callback_arg, dmat->segments, 0, 0, error); 866 } else { 867 (*callback)(callback_arg, dmat->segments, 868 nsegs+1, uio->uio_resid, error); 869 } 870 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 871 __func__, dmat, dmat->flags, error, nsegs + 1); 872 return (error); 873} 874 875/* 876 * Release the mapping held by map. 877 */ 878void 879_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 880{ 881 struct bounce_page *bpage; 882 883 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 884 STAILQ_REMOVE_HEAD(&map->bpages, links); 885 free_bounce_page(dmat, bpage); 886 } 887} 888 889void 890_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 891{ 892 struct bounce_page *bpage; 893 894 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 895 /* 896 * Handle data bouncing. We might also 897 * want to add support for invalidating 898 * the caches on broken hardware 899 */ 900 dmat->bounce_zone->total_bounced++; 901 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 902 "performing bounce", __func__, op, dmat, dmat->flags); 903 904 if (op & BUS_DMASYNC_PREWRITE) { 905 while (bpage != NULL) { 906 bcopy((void *)bpage->datavaddr, 907 (void *)bpage->vaddr, 908 bpage->datacount); 909 bpage = STAILQ_NEXT(bpage, links); 910 } 911 } 912 913 if (op & BUS_DMASYNC_POSTREAD) { 914 while (bpage != NULL) { 915 bcopy((void *)bpage->vaddr, 916 (void *)bpage->datavaddr, 917 bpage->datacount); 918 bpage = STAILQ_NEXT(bpage, links); 919 } 920 } 921 } 922} 923 924static void 925init_bounce_pages(void *dummy __unused) 926{ 927 928 total_bpages = 0; 929 STAILQ_INIT(&bounce_zone_list); 930 STAILQ_INIT(&bounce_map_waitinglist); 931 STAILQ_INIT(&bounce_map_callbacklist); 932 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 933} 934SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 935 936static struct sysctl_ctx_list * 937busdma_sysctl_tree(struct bounce_zone *bz) 938{ 939 return (&bz->sysctl_tree); 940} 941 942static struct sysctl_oid * 943busdma_sysctl_tree_top(struct bounce_zone *bz) 944{ 945 return (bz->sysctl_tree_top); 946} 947 948static int 949alloc_bounce_zone(bus_dma_tag_t dmat) 950{ 951 struct bounce_zone *bz; 952 953 /* Check to see if we already have a suitable zone */ 954 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 955 if ((dmat->alignment <= bz->alignment) 956 && (dmat->boundary <= bz->boundary) 957 && (dmat->lowaddr >= bz->lowaddr)) { 958 dmat->bounce_zone = bz; 959 return (0); 960 } 961 } 962 963 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 964 M_NOWAIT | M_ZERO)) == NULL) 965 return (ENOMEM); 966 967 STAILQ_INIT(&bz->bounce_page_list); 968 bz->free_bpages = 0; 969 bz->reserved_bpages = 0; 970 bz->active_bpages = 0; 971 bz->lowaddr = dmat->lowaddr; 972 bz->alignment = dmat->alignment; 973 bz->boundary = dmat->boundary; 974 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 975 busdma_zonecount++; 976 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 977 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 978 dmat->bounce_zone = bz; 979 980 sysctl_ctx_init(&bz->sysctl_tree); 981 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 982 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 983 CTLFLAG_RD, 0, ""); 984 if (bz->sysctl_tree_top == NULL) { 985 sysctl_ctx_free(&bz->sysctl_tree); 986 return (0); /* XXX error code? */ 987 } 988 989 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 990 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 991 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 992 "Total bounce pages"); 993 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 994 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 995 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 996 "Free bounce pages"); 997 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 998 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 999 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1000 "Reserved bounce pages"); 1001 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1002 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1003 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1004 "Active bounce pages"); 1005 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1006 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1007 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1008 "Total bounce requests"); 1009 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1010 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1011 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1012 "Total bounce requests that were deferred"); 1013 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1014 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1015 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1016 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1017 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1018 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1019 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1020 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1021 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 1022 1023 return (0); 1024} 1025 1026static int 1027alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1028{ 1029 struct bounce_zone *bz; 1030 int count; 1031 1032 bz = dmat->bounce_zone; 1033 count = 0; 1034 while (numpages > 0) { 1035 struct bounce_page *bpage; 1036 1037 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1038 M_NOWAIT | M_ZERO); 1039 1040 if (bpage == NULL) 1041 break; 1042 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1043 M_NOWAIT, 0ul, 1044 bz->lowaddr, 1045 PAGE_SIZE, 1046 bz->boundary); 1047 if (bpage->vaddr == 0) { 1048 free(bpage, M_DEVBUF); 1049 break; 1050 } 1051 bpage->busaddr = pmap_kextract(bpage->vaddr); 1052 mtx_lock(&bounce_lock); 1053 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1054 total_bpages++; 1055 bz->total_bpages++; 1056 bz->free_bpages++; 1057 mtx_unlock(&bounce_lock); 1058 count++; 1059 numpages--; 1060 } 1061 return (count); 1062} 1063 1064static int 1065reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1066{ 1067 struct bounce_zone *bz; 1068 int pages; 1069 1070 mtx_assert(&bounce_lock, MA_OWNED); 1071 bz = dmat->bounce_zone; 1072 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1073 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1074 return (map->pagesneeded - (map->pagesreserved + pages)); 1075 bz->free_bpages -= pages; 1076 bz->reserved_bpages += pages; 1077 map->pagesreserved += pages; 1078 pages = map->pagesneeded - map->pagesreserved; 1079 1080 return (pages); 1081} 1082 1083static bus_addr_t 1084add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1085 bus_size_t size) 1086{ 1087 struct bounce_zone *bz; 1088 struct bounce_page *bpage; 1089 1090 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1091 KASSERT(map != NULL && map != &nobounce_dmamap, 1092 ("add_bounce_page: bad map %p", map)); 1093 1094 bz = dmat->bounce_zone; 1095 if (map->pagesneeded == 0) 1096 panic("add_bounce_page: map doesn't need any pages"); 1097 map->pagesneeded--; 1098 1099 if (map->pagesreserved == 0) 1100 panic("add_bounce_page: map doesn't need any pages"); 1101 map->pagesreserved--; 1102 1103 mtx_lock(&bounce_lock); 1104 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1105 if (bpage == NULL) 1106 panic("add_bounce_page: free page list is empty"); 1107 1108 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1109 bz->reserved_bpages--; 1110 bz->active_bpages++; 1111 mtx_unlock(&bounce_lock); 1112 1113 bpage->datavaddr = vaddr; 1114 bpage->datacount = size; 1115 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1116 return (bpage->busaddr); 1117} 1118 1119static void 1120free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1121{ 1122 struct bus_dmamap *map; 1123 struct bounce_zone *bz; 1124 1125 bz = dmat->bounce_zone; 1126 bpage->datavaddr = 0; 1127 bpage->datacount = 0; 1128 1129 mtx_lock(&bounce_lock); 1130 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1131 bz->free_bpages++; 1132 bz->active_bpages--; 1133 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1134 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1135 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1136 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1137 map, links); 1138 busdma_swi_pending = 1; 1139 bz->total_deferred++; 1140 swi_sched(vm_ih, 0); 1141 } 1142 } 1143 mtx_unlock(&bounce_lock); 1144} 1145 1146void 1147busdma_swi(void) 1148{ 1149 bus_dma_tag_t dmat; 1150 struct bus_dmamap *map; 1151 1152 mtx_lock(&bounce_lock); 1153 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1154 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1155 mtx_unlock(&bounce_lock); 1156 dmat = map->dmat; 1157 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1158 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1159 map->callback, map->callback_arg, /*flags*/0); 1160 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1161 mtx_lock(&bounce_lock); 1162 } 1163 mtx_unlock(&bounce_lock); 1164} 1165