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("$FreeBSD$"); 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 #ifdef __i386__ 54 #define MAX_BPAGES 512 55 #else 56 #define MAX_BPAGES 8192 57 #endif 58 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 59 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 60 61 struct bounce_zone; 62 63 struct bus_dma_tag { 64 bus_dma_tag_t parent; 65 bus_size_t alignment; 66 bus_size_t boundary; 67 bus_addr_t lowaddr; 68 bus_addr_t highaddr; 69 bus_dma_filter_t *filter; 70 void *filterarg; 71 bus_size_t maxsize; 72 u_int nsegments; 73 bus_size_t maxsegsz; 74 int flags; 75 int ref_count; 76 int map_count; 77 bus_dma_lock_t *lockfunc; 78 void *lockfuncarg; 79 bus_dma_segment_t *segments; 80 struct bounce_zone *bounce_zone; 81 }; 82 83 struct bounce_page { 84 vm_offset_t vaddr; /* kva of bounce buffer */ 85 bus_addr_t busaddr; /* Physical address */ 86 vm_offset_t datavaddr; /* kva 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 bus_size_t alignment; 104 bus_addr_t lowaddr; 105 char zoneid[8]; 106 char lowaddrid[20]; 107 struct sysctl_ctx_list sysctl_tree; 108 struct sysctl_oid *sysctl_tree_top; 109 }; 110 111 static struct mtx bounce_lock; 112 static int total_bpages; 113 static int busdma_zonecount; 114 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 115 116 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 117 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 118 "Total bounce pages"); 119 120 struct bus_dmamap { 121 struct bp_list bpages; 122 int pagesneeded; 123 int pagesreserved; 124 bus_dma_tag_t dmat; 125 void *buf; /* unmapped buffer pointer */ 126 bus_size_t buflen; /* unmapped buffer length */ 127 bus_dmamap_callback_t *callback; 128 void *callback_arg; 129 STAILQ_ENTRY(bus_dmamap) links; 130 }; 131 132 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 133 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 134 static struct bus_dmamap nobounce_dmamap; 135 136 static void init_bounce_pages(void *dummy); 137 static int alloc_bounce_zone(bus_dma_tag_t dmat); 138 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 139 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 140 int commit); 141 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 142 vm_offset_t vaddr, bus_size_t size); 143 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 144 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 145 int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 146 void *buf, bus_size_t buflen, int flags); 147 148 #ifdef XEN 149 #undef pmap_kextract 150 #define pmap_kextract pmap_kextract_ma 151 #endif 152 153 /* 154 * Return true if a match is made. 155 * 156 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 157 * 158 * If paddr is within the bounds of the dma tag then call the filter callback 159 * to check for a match, if there is no filter callback then assume a match. 160 */ 161 int 162 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 163 { 164 int retval; 165 166 retval = 0; 167 168 do { 169 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 170 || ((paddr & (dmat->alignment - 1)) != 0)) 171 && (dmat->filter == NULL 172 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 173 retval = 1; 174 175 dmat = dmat->parent; 176 } while (retval == 0 && dmat != NULL); 177 return (retval); 178 } 179 180 /* 181 * Convenience function for manipulating driver locks from busdma (during 182 * busdma_swi, for example). Drivers that don't provide their own locks 183 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 184 * non-mutex locking scheme don't have to use this at all. 185 */ 186 void 187 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 188 { 189 struct mtx *dmtx; 190 191 dmtx = (struct mtx *)arg; 192 switch (op) { 193 case BUS_DMA_LOCK: 194 mtx_lock(dmtx); 195 break; 196 case BUS_DMA_UNLOCK: 197 mtx_unlock(dmtx); 198 break; 199 default: 200 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 201 } 202 } 203 204 /* 205 * dflt_lock should never get called. It gets put into the dma tag when 206 * lockfunc == NULL, which is only valid if the maps that are associated 207 * with the tag are meant to never be defered. 208 * XXX Should have a way to identify which driver is responsible here. 209 */ 210 static void 211 dflt_lock(void *arg, bus_dma_lock_op_t op) 212 { 213 panic("driver error: busdma dflt_lock called"); 214 } 215 216 /* 217 * Allocate a device specific dma_tag. 218 */ 219 int 220 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 221 bus_size_t boundary, bus_addr_t lowaddr, 222 bus_addr_t highaddr, bus_dma_filter_t *filter, 223 void *filterarg, bus_size_t maxsize, int nsegments, 224 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 225 void *lockfuncarg, bus_dma_tag_t *dmat) 226 { 227 bus_dma_tag_t newtag; 228 int error = 0; 229 230 /* Basic sanity checking */ 231 if (boundary != 0 && boundary < maxsegsz) 232 maxsegsz = boundary; 233 234 if (maxsegsz == 0) { 235 return (EINVAL); 236 } 237 238 /* Return a NULL tag on failure */ 239 *dmat = NULL; 240 241 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 242 M_ZERO | M_NOWAIT); 243 if (newtag == NULL) { 244 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 245 __func__, newtag, 0, error); 246 return (ENOMEM); 247 } 248 249 newtag->parent = parent; 250 newtag->alignment = alignment; 251 newtag->boundary = boundary; 252 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 253 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 254 newtag->filter = filter; 255 newtag->filterarg = filterarg; 256 newtag->maxsize = maxsize; 257 newtag->nsegments = nsegments; 258 newtag->maxsegsz = maxsegsz; 259 newtag->flags = flags; 260 newtag->ref_count = 1; /* Count ourself */ 261 newtag->map_count = 0; 262 if (lockfunc != NULL) { 263 newtag->lockfunc = lockfunc; 264 newtag->lockfuncarg = lockfuncarg; 265 } else { 266 newtag->lockfunc = dflt_lock; 267 newtag->lockfuncarg = NULL; 268 } 269 newtag->segments = NULL; 270 271 /* Take into account any restrictions imposed by our parent tag */ 272 if (parent != NULL) { 273 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 274 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 275 if (newtag->boundary == 0) 276 newtag->boundary = parent->boundary; 277 else if (parent->boundary != 0) 278 newtag->boundary = MIN(parent->boundary, 279 newtag->boundary); 280 if ((newtag->filter != NULL) || 281 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0)) 282 newtag->flags |= BUS_DMA_COULD_BOUNCE; 283 if (newtag->filter == NULL) { 284 /* 285 * Short circuit looking at our parent directly 286 * since we have encapsulated all of its information 287 */ 288 newtag->filter = parent->filter; 289 newtag->filterarg = parent->filterarg; 290 newtag->parent = parent->parent; 291 } 292 if (newtag->parent != NULL) 293 atomic_add_int(&parent->ref_count, 1); 294 } 295 296 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 297 || newtag->alignment > 1) 298 newtag->flags |= BUS_DMA_COULD_BOUNCE; 299 300 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 301 (flags & BUS_DMA_ALLOCNOW) != 0) { 302 struct bounce_zone *bz; 303 304 /* Must bounce */ 305 306 if ((error = alloc_bounce_zone(newtag)) != 0) { 307 free(newtag, M_DEVBUF); 308 return (error); 309 } 310 bz = newtag->bounce_zone; 311 312 if (ptoa(bz->total_bpages) < maxsize) { 313 int pages; 314 315 pages = atop(maxsize) - bz->total_bpages; 316 317 /* Add pages to our bounce pool */ 318 if (alloc_bounce_pages(newtag, pages) < pages) 319 error = ENOMEM; 320 } 321 /* Performed initial allocation */ 322 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 323 } 324 325 if (error != 0) { 326 free(newtag, M_DEVBUF); 327 } else { 328 *dmat = newtag; 329 } 330 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 331 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 332 return (error); 333 } 334 335 int 336 bus_dma_tag_destroy(bus_dma_tag_t dmat) 337 { 338 bus_dma_tag_t dmat_copy; 339 int error; 340 341 error = 0; 342 dmat_copy = dmat; 343 344 if (dmat != NULL) { 345 346 if (dmat->map_count != 0) { 347 error = EBUSY; 348 goto out; 349 } 350 351 while (dmat != NULL) { 352 bus_dma_tag_t parent; 353 354 parent = dmat->parent; 355 atomic_subtract_int(&dmat->ref_count, 1); 356 if (dmat->ref_count == 0) { 357 if (dmat->segments != NULL) 358 free(dmat->segments, M_DEVBUF); 359 free(dmat, M_DEVBUF); 360 /* 361 * Last reference count, so 362 * release our reference 363 * count on our parent. 364 */ 365 dmat = parent; 366 } else 367 dmat = NULL; 368 } 369 } 370 out: 371 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 372 return (error); 373 } 374 375 /* 376 * Allocate a handle for mapping from kva/uva/physical 377 * address space into bus device space. 378 */ 379 int 380 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 381 { 382 int error; 383 384 error = 0; 385 386 if (dmat->segments == NULL) { 387 dmat->segments = (bus_dma_segment_t *)malloc( 388 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 389 M_NOWAIT); 390 if (dmat->segments == NULL) { 391 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 392 __func__, dmat, ENOMEM); 393 return (ENOMEM); 394 } 395 } 396 397 /* 398 * Bouncing might be required if the driver asks for an active 399 * exclusion region, a data alignment that is stricter than 1, and/or 400 * an active address boundary. 401 */ 402 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 403 404 /* Must bounce */ 405 struct bounce_zone *bz; 406 int maxpages; 407 408 if (dmat->bounce_zone == NULL) { 409 if ((error = alloc_bounce_zone(dmat)) != 0) 410 return (error); 411 } 412 bz = dmat->bounce_zone; 413 414 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 415 M_NOWAIT | M_ZERO); 416 if (*mapp == NULL) { 417 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 418 __func__, dmat, ENOMEM); 419 return (ENOMEM); 420 } 421 422 /* Initialize the new map */ 423 STAILQ_INIT(&((*mapp)->bpages)); 424 425 /* 426 * Attempt to add pages to our pool on a per-instance 427 * basis up to a sane limit. 428 */ 429 if (dmat->alignment > 1) 430 maxpages = MAX_BPAGES; 431 else 432 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 433 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 434 || (bz->map_count > 0 && bz->total_bpages < maxpages)) { 435 int pages; 436 437 pages = MAX(atop(dmat->maxsize), 1); 438 pages = MIN(maxpages - bz->total_bpages, pages); 439 pages = MAX(pages, 1); 440 if (alloc_bounce_pages(dmat, pages) < pages) 441 error = ENOMEM; 442 443 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 444 if (error == 0) 445 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 446 } else { 447 error = 0; 448 } 449 } 450 bz->map_count++; 451 } else { 452 *mapp = NULL; 453 } 454 if (error == 0) 455 dmat->map_count++; 456 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 457 __func__, dmat, dmat->flags, error); 458 return (error); 459 } 460 461 /* 462 * Destroy a handle for mapping from kva/uva/physical 463 * address space into bus device space. 464 */ 465 int 466 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 467 { 468 if (map != NULL && map != &nobounce_dmamap) { 469 if (STAILQ_FIRST(&map->bpages) != NULL) { 470 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 471 __func__, dmat, EBUSY); 472 return (EBUSY); 473 } 474 if (dmat->bounce_zone) 475 dmat->bounce_zone->map_count--; 476 free(map, M_DEVBUF); 477 } 478 dmat->map_count--; 479 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 480 return (0); 481 } 482 483 484 /* 485 * Allocate a piece of memory that can be efficiently mapped into 486 * bus device space based on the constraints lited in the dma tag. 487 * A dmamap to for use with dmamap_load is also allocated. 488 */ 489 int 490 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 491 bus_dmamap_t *mapp) 492 { 493 int mflags; 494 495 if (flags & BUS_DMA_NOWAIT) 496 mflags = M_NOWAIT; 497 else 498 mflags = M_WAITOK; 499 500 /* If we succeed, no mapping/bouncing will be required */ 501 *mapp = NULL; 502 503 if (dmat->segments == NULL) { 504 dmat->segments = (bus_dma_segment_t *)malloc( 505 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 506 mflags); 507 if (dmat->segments == NULL) { 508 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 509 __func__, dmat, dmat->flags, ENOMEM); 510 return (ENOMEM); 511 } 512 } 513 if (flags & BUS_DMA_ZERO) 514 mflags |= M_ZERO; 515 516 /* 517 * XXX: 518 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 519 * alignment guarantees of malloc need to be nailed down, and the 520 * code below should be rewritten to take that into account. 521 * 522 * In the meantime, we'll warn the user if malloc gets it wrong. 523 */ 524 if ((dmat->maxsize <= PAGE_SIZE) && 525 (dmat->alignment < dmat->maxsize) && 526 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 527 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 528 } else { 529 /* 530 * XXX Use Contigmalloc until it is merged into this facility 531 * and handles multi-seg allocations. Nobody is doing 532 * multi-seg allocations yet though. 533 * XXX Certain AGP hardware does. 534 */ 535 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 536 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 537 dmat->boundary); 538 } 539 if (*vaddr == NULL) { 540 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 541 __func__, dmat, dmat->flags, ENOMEM); 542 return (ENOMEM); 543 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) { 544 printf("bus_dmamem_alloc failed to align memory properly.\n"); 545 } 546 if (flags & BUS_DMA_NOCACHE) 547 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 548 PAT_UNCACHEABLE); 549 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 550 __func__, dmat, dmat->flags, 0); 551 return (0); 552 } 553 554 /* 555 * Free a piece of memory and it's allociated dmamap, that was allocated 556 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 557 */ 558 void 559 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 560 { 561 /* 562 * dmamem does not need to be bounced, so the map should be 563 * NULL 564 */ 565 if (map != NULL) 566 panic("bus_dmamem_free: Invalid map freed\n"); 567 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 568 if ((dmat->maxsize <= PAGE_SIZE) && 569 (dmat->alignment < dmat->maxsize) && 570 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 571 free(vaddr, M_DEVBUF); 572 else { 573 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 574 } 575 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 576 } 577 578 int 579 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 580 void *buf, bus_size_t buflen, int flags) 581 { 582 vm_offset_t vaddr; 583 vm_offset_t vendaddr; 584 bus_addr_t paddr; 585 586 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 587 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 588 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 589 dmat->boundary, dmat->alignment); 590 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 591 map, &nobounce_dmamap, map->pagesneeded); 592 /* 593 * Count the number of bounce pages 594 * needed in order to complete this transfer 595 */ 596 vaddr = (vm_offset_t)buf; 597 vendaddr = (vm_offset_t)buf + buflen; 598 599 while (vaddr < vendaddr) { 600 bus_size_t sg_len; 601 602 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 603 if (pmap) 604 paddr = pmap_extract(pmap, vaddr); 605 else 606 paddr = pmap_kextract(vaddr); 607 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 608 run_filter(dmat, paddr) != 0) { 609 sg_len = roundup2(sg_len, dmat->alignment); 610 map->pagesneeded++; 611 } 612 vaddr += sg_len; 613 } 614 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 615 } 616 617 /* Reserve Necessary Bounce Pages */ 618 if (map->pagesneeded != 0) { 619 mtx_lock(&bounce_lock); 620 if (flags & BUS_DMA_NOWAIT) { 621 if (reserve_bounce_pages(dmat, map, 0) != 0) { 622 mtx_unlock(&bounce_lock); 623 return (ENOMEM); 624 } 625 } else { 626 if (reserve_bounce_pages(dmat, map, 1) != 0) { 627 /* Queue us for resources */ 628 map->dmat = dmat; 629 map->buf = buf; 630 map->buflen = buflen; 631 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 632 map, links); 633 mtx_unlock(&bounce_lock); 634 return (EINPROGRESS); 635 } 636 } 637 mtx_unlock(&bounce_lock); 638 } 639 640 return (0); 641 } 642 643 /* 644 * Utility function to load a linear buffer. lastaddrp holds state 645 * between invocations (for multiple-buffer loads). segp contains 646 * the starting segment on entrace, and the ending segment on exit. 647 * first indicates if this is the first invocation of this function. 648 */ 649 static __inline int 650 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 651 bus_dmamap_t map, 652 void *buf, bus_size_t buflen, 653 pmap_t pmap, 654 int flags, 655 bus_addr_t *lastaddrp, 656 bus_dma_segment_t *segs, 657 int *segp, 658 int first) 659 { 660 bus_size_t sgsize; 661 bus_addr_t curaddr, lastaddr, baddr, bmask; 662 vm_offset_t vaddr; 663 int seg, error; 664 665 if (map == NULL) 666 map = &nobounce_dmamap; 667 668 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) { 669 error = _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 670 if (error) 671 return (error); 672 } 673 674 vaddr = (vm_offset_t)buf; 675 lastaddr = *lastaddrp; 676 bmask = ~(dmat->boundary - 1); 677 678 for (seg = *segp; buflen > 0 ; ) { 679 bus_size_t max_sgsize; 680 681 /* 682 * Get the physical address for this segment. 683 */ 684 if (pmap) 685 curaddr = pmap_extract(pmap, vaddr); 686 else 687 curaddr = pmap_kextract(vaddr); 688 689 /* 690 * Compute the segment size, and adjust counts. 691 */ 692 max_sgsize = MIN(buflen, dmat->maxsegsz); 693 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); 694 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 695 map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 696 sgsize = roundup2(sgsize, dmat->alignment); 697 sgsize = MIN(sgsize, max_sgsize); 698 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 699 } else { 700 sgsize = MIN(sgsize, max_sgsize); 701 } 702 703 /* 704 * Make sure we don't cross any boundaries. 705 */ 706 if (dmat->boundary > 0) { 707 baddr = (curaddr + dmat->boundary) & bmask; 708 if (sgsize > (baddr - curaddr)) 709 sgsize = (baddr - curaddr); 710 } 711 712 /* 713 * Insert chunk into a segment, coalescing with 714 * previous segment if possible. 715 */ 716 if (first) { 717 segs[seg].ds_addr = curaddr; 718 segs[seg].ds_len = sgsize; 719 first = 0; 720 } else { 721 if (curaddr == lastaddr && 722 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 723 (dmat->boundary == 0 || 724 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 725 segs[seg].ds_len += sgsize; 726 else { 727 if (++seg >= dmat->nsegments) 728 break; 729 segs[seg].ds_addr = curaddr; 730 segs[seg].ds_len = sgsize; 731 } 732 } 733 734 lastaddr = curaddr + sgsize; 735 vaddr += sgsize; 736 buflen -= sgsize; 737 } 738 739 *segp = seg; 740 *lastaddrp = lastaddr; 741 742 /* 743 * Did we fit? 744 */ 745 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 746 } 747 748 /* 749 * Map the buffer buf into bus space using the dmamap map. 750 */ 751 int 752 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 753 bus_size_t buflen, bus_dmamap_callback_t *callback, 754 void *callback_arg, int flags) 755 { 756 bus_addr_t lastaddr = 0; 757 int error, nsegs = 0; 758 759 if (map != NULL) { 760 flags |= BUS_DMA_WAITOK; 761 map->callback = callback; 762 map->callback_arg = callback_arg; 763 } 764 765 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 766 &lastaddr, dmat->segments, &nsegs, 1); 767 768 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 769 __func__, dmat, dmat->flags, error, nsegs + 1); 770 771 if (error == EINPROGRESS) { 772 return (error); 773 } 774 775 if (error) 776 (*callback)(callback_arg, dmat->segments, 0, error); 777 else 778 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 779 780 /* 781 * Return ENOMEM to the caller so that it can pass it up the stack. 782 * This error only happens when NOWAIT is set, so deferal is disabled. 783 */ 784 if (error == ENOMEM) 785 return (error); 786 787 return (0); 788 } 789 790 791 /* 792 * Like _bus_dmamap_load(), but for mbufs. 793 */ 794 static __inline int 795 _bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 796 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 797 int flags) 798 { 799 int error; 800 801 M_ASSERTPKTHDR(m0); 802 803 flags |= BUS_DMA_NOWAIT; 804 *nsegs = 0; 805 error = 0; 806 if (m0->m_pkthdr.len <= dmat->maxsize) { 807 int first = 1; 808 bus_addr_t lastaddr = 0; 809 struct mbuf *m; 810 811 for (m = m0; m != NULL && error == 0; m = m->m_next) { 812 if (m->m_len > 0) { 813 error = _bus_dmamap_load_buffer(dmat, map, 814 m->m_data, m->m_len, 815 NULL, flags, &lastaddr, 816 segs, nsegs, first); 817 first = 0; 818 } 819 } 820 } else { 821 error = EINVAL; 822 } 823 824 /* XXX FIXME: Having to increment nsegs is really annoying */ 825 ++*nsegs; 826 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 827 __func__, dmat, dmat->flags, error, *nsegs); 828 return (error); 829 } 830 831 int 832 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 833 struct mbuf *m0, 834 bus_dmamap_callback2_t *callback, void *callback_arg, 835 int flags) 836 { 837 int nsegs, error; 838 839 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs, 840 flags); 841 842 if (error) { 843 /* force "no valid mappings" in callback */ 844 (*callback)(callback_arg, dmat->segments, 0, 0, error); 845 } else { 846 (*callback)(callback_arg, dmat->segments, 847 nsegs, m0->m_pkthdr.len, error); 848 } 849 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 850 __func__, dmat, dmat->flags, error, nsegs); 851 return (error); 852 } 853 854 int 855 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 856 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 857 int flags) 858 { 859 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags)); 860 } 861 862 /* 863 * Like _bus_dmamap_load(), but for uios. 864 */ 865 int 866 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 867 struct uio *uio, 868 bus_dmamap_callback2_t *callback, void *callback_arg, 869 int flags) 870 { 871 bus_addr_t lastaddr = 0; 872 int nsegs, error, first, i; 873 bus_size_t resid; 874 struct iovec *iov; 875 pmap_t pmap; 876 877 flags |= BUS_DMA_NOWAIT; 878 resid = uio->uio_resid; 879 iov = uio->uio_iov; 880 881 if (uio->uio_segflg == UIO_USERSPACE) { 882 KASSERT(uio->uio_td != NULL, 883 ("bus_dmamap_load_uio: USERSPACE but no proc")); 884 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 885 } else 886 pmap = NULL; 887 888 nsegs = 0; 889 error = 0; 890 first = 1; 891 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 892 /* 893 * Now at the first iovec to load. Load each iovec 894 * until we have exhausted the residual count. 895 */ 896 bus_size_t minlen = 897 resid < iov[i].iov_len ? resid : iov[i].iov_len; 898 caddr_t addr = (caddr_t) iov[i].iov_base; 899 900 if (minlen > 0) { 901 error = _bus_dmamap_load_buffer(dmat, map, 902 addr, minlen, pmap, flags, &lastaddr, 903 dmat->segments, &nsegs, first); 904 first = 0; 905 906 resid -= minlen; 907 } 908 } 909 910 if (error) { 911 /* force "no valid mappings" in callback */ 912 (*callback)(callback_arg, dmat->segments, 0, 0, error); 913 } else { 914 (*callback)(callback_arg, dmat->segments, 915 nsegs+1, uio->uio_resid, error); 916 } 917 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 918 __func__, dmat, dmat->flags, error, nsegs + 1); 919 return (error); 920 } 921 922 /* 923 * Release the mapping held by map. 924 */ 925 void 926 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 927 { 928 struct bounce_page *bpage; 929 930 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 931 STAILQ_REMOVE_HEAD(&map->bpages, links); 932 free_bounce_page(dmat, bpage); 933 } 934 } 935 936 void 937 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 938 { 939 struct bounce_page *bpage; 940 941 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 942 /* 943 * Handle data bouncing. We might also 944 * want to add support for invalidating 945 * the caches on broken hardware 946 */ 947 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 948 "performing bounce", __func__, op, dmat, dmat->flags); 949 950 if (op & BUS_DMASYNC_PREWRITE) { 951 while (bpage != NULL) { 952 bcopy((void *)bpage->datavaddr, 953 (void *)bpage->vaddr, 954 bpage->datacount); 955 bpage = STAILQ_NEXT(bpage, links); 956 } 957 dmat->bounce_zone->total_bounced++; 958 } 959 960 if (op & BUS_DMASYNC_POSTREAD) { 961 while (bpage != NULL) { 962 bcopy((void *)bpage->vaddr, 963 (void *)bpage->datavaddr, 964 bpage->datacount); 965 bpage = STAILQ_NEXT(bpage, links); 966 } 967 dmat->bounce_zone->total_bounced++; 968 } 969 } 970 } 971 972 static void 973 init_bounce_pages(void *dummy __unused) 974 { 975 976 total_bpages = 0; 977 STAILQ_INIT(&bounce_zone_list); 978 STAILQ_INIT(&bounce_map_waitinglist); 979 STAILQ_INIT(&bounce_map_callbacklist); 980 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 981 } 982 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 983 984 static struct sysctl_ctx_list * 985 busdma_sysctl_tree(struct bounce_zone *bz) 986 { 987 return (&bz->sysctl_tree); 988 } 989 990 static struct sysctl_oid * 991 busdma_sysctl_tree_top(struct bounce_zone *bz) 992 { 993 return (bz->sysctl_tree_top); 994 } 995 996 #if defined(__amd64__) || defined(PAE) 997 #define SYSCTL_ADD_BUS_SIZE_T SYSCTL_ADD_UQUAD 998 #else 999 #define SYSCTL_ADD_BUS_SIZE_T(ctx, parent, nbr, name, flag, ptr, desc) \ 1000 SYSCTL_ADD_UINT(ctx, parent, nbr, name, flag, ptr, 0, desc) 1001 #endif 1002 1003 static int 1004 alloc_bounce_zone(bus_dma_tag_t dmat) 1005 { 1006 struct bounce_zone *bz; 1007 1008 /* Check to see if we already have a suitable zone */ 1009 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1010 if ((dmat->alignment <= bz->alignment) 1011 && (dmat->lowaddr >= bz->lowaddr)) { 1012 dmat->bounce_zone = bz; 1013 return (0); 1014 } 1015 } 1016 1017 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1018 M_NOWAIT | M_ZERO)) == NULL) 1019 return (ENOMEM); 1020 1021 STAILQ_INIT(&bz->bounce_page_list); 1022 bz->free_bpages = 0; 1023 bz->reserved_bpages = 0; 1024 bz->active_bpages = 0; 1025 bz->lowaddr = dmat->lowaddr; 1026 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 1027 bz->map_count = 0; 1028 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1029 busdma_zonecount++; 1030 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1031 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1032 dmat->bounce_zone = bz; 1033 1034 sysctl_ctx_init(&bz->sysctl_tree); 1035 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1036 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1037 CTLFLAG_RD, 0, ""); 1038 if (bz->sysctl_tree_top == NULL) { 1039 sysctl_ctx_free(&bz->sysctl_tree); 1040 return (0); /* XXX error code? */ 1041 } 1042 1043 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1045 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1046 "Total bounce pages"); 1047 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1048 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1049 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1050 "Free bounce pages"); 1051 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1052 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1053 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1054 "Reserved bounce pages"); 1055 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1056 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1057 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1058 "Active bounce pages"); 1059 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1060 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1061 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1062 "Total bounce requests"); 1063 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1064 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1065 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1066 "Total bounce requests that were deferred"); 1067 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1068 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1069 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1070 SYSCTL_ADD_BUS_SIZE_T(busdma_sysctl_tree(bz), 1071 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1072 "alignment", CTLFLAG_RD, &bz->alignment, ""); 1073 1074 return (0); 1075 } 1076 1077 static int 1078 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1079 { 1080 struct bounce_zone *bz; 1081 int count; 1082 1083 bz = dmat->bounce_zone; 1084 count = 0; 1085 while (numpages > 0) { 1086 struct bounce_page *bpage; 1087 1088 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1089 M_NOWAIT | M_ZERO); 1090 1091 if (bpage == NULL) 1092 break; 1093 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1094 M_NOWAIT, 0ul, 1095 bz->lowaddr, 1096 PAGE_SIZE, 1097 0); 1098 if (bpage->vaddr == 0) { 1099 free(bpage, M_DEVBUF); 1100 break; 1101 } 1102 bpage->busaddr = pmap_kextract(bpage->vaddr); 1103 mtx_lock(&bounce_lock); 1104 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1105 total_bpages++; 1106 bz->total_bpages++; 1107 bz->free_bpages++; 1108 mtx_unlock(&bounce_lock); 1109 count++; 1110 numpages--; 1111 } 1112 return (count); 1113 } 1114 1115 static int 1116 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1117 { 1118 struct bounce_zone *bz; 1119 int pages; 1120 1121 mtx_assert(&bounce_lock, MA_OWNED); 1122 bz = dmat->bounce_zone; 1123 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1124 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1125 return (map->pagesneeded - (map->pagesreserved + pages)); 1126 bz->free_bpages -= pages; 1127 bz->reserved_bpages += pages; 1128 map->pagesreserved += pages; 1129 pages = map->pagesneeded - map->pagesreserved; 1130 1131 return (pages); 1132 } 1133 1134 static bus_addr_t 1135 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1136 bus_size_t size) 1137 { 1138 struct bounce_zone *bz; 1139 struct bounce_page *bpage; 1140 1141 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1142 KASSERT(map != NULL && map != &nobounce_dmamap, 1143 ("add_bounce_page: bad map %p", map)); 1144 1145 bz = dmat->bounce_zone; 1146 if (map->pagesneeded == 0) 1147 panic("add_bounce_page: map doesn't need any pages"); 1148 map->pagesneeded--; 1149 1150 if (map->pagesreserved == 0) 1151 panic("add_bounce_page: map doesn't need any pages"); 1152 map->pagesreserved--; 1153 1154 mtx_lock(&bounce_lock); 1155 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1156 if (bpage == NULL) 1157 panic("add_bounce_page: free page list is empty"); 1158 1159 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1160 bz->reserved_bpages--; 1161 bz->active_bpages++; 1162 mtx_unlock(&bounce_lock); 1163 1164 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1165 /* Page offset needs to be preserved. */ 1166 bpage->vaddr |= vaddr & PAGE_MASK; 1167 bpage->busaddr |= vaddr & PAGE_MASK; 1168 } 1169 bpage->datavaddr = vaddr; 1170 bpage->datacount = size; 1171 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1172 return (bpage->busaddr); 1173 } 1174 1175 static void 1176 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1177 { 1178 struct bus_dmamap *map; 1179 struct bounce_zone *bz; 1180 1181 bz = dmat->bounce_zone; 1182 bpage->datavaddr = 0; 1183 bpage->datacount = 0; 1184 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1185 /* 1186 * Reset the bounce page to start at offset 0. Other uses 1187 * of this bounce page may need to store a full page of 1188 * data and/or assume it starts on a page boundary. 1189 */ 1190 bpage->vaddr &= ~PAGE_MASK; 1191 bpage->busaddr &= ~PAGE_MASK; 1192 } 1193 1194 mtx_lock(&bounce_lock); 1195 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1196 bz->free_bpages++; 1197 bz->active_bpages--; 1198 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1199 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1200 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1201 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1202 map, links); 1203 busdma_swi_pending = 1; 1204 bz->total_deferred++; 1205 swi_sched(vm_ih, 0); 1206 } 1207 } 1208 mtx_unlock(&bounce_lock); 1209 } 1210 1211 void 1212 busdma_swi(void) 1213 { 1214 bus_dma_tag_t dmat; 1215 struct bus_dmamap *map; 1216 1217 mtx_lock(&bounce_lock); 1218 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1219 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1220 mtx_unlock(&bounce_lock); 1221 dmat = map->dmat; 1222 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1223 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1224 map->callback, map->callback_arg, /*flags*/0); 1225 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1226 mtx_lock(&bounce_lock); 1227 } 1228 mtx_unlock(&bounce_lock); 1229 } 1230