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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/7.4/sys/amd64/amd64/busdma_machdep.c 200289 2009-12-09 08:16:12Z scottl $"); 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 bus_size_t alignment; 97 bus_addr_t lowaddr; 98 char zoneid[8]; 99 char lowaddrid[20]; 100 struct sysctl_ctx_list sysctl_tree; 101 struct sysctl_oid *sysctl_tree_top; 102 }; 103 104 static struct mtx bounce_lock; 105 static int total_bpages; 106 static int busdma_zonecount; 107 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 108 109 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 110 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 111 "Total bounce pages"); 112 113 struct bus_dmamap { 114 struct bp_list bpages; 115 int pagesneeded; 116 int pagesreserved; 117 bus_dma_tag_t dmat; 118 void *buf; /* unmapped buffer pointer */ 119 bus_size_t buflen; /* unmapped buffer length */ 120 bus_dmamap_callback_t *callback; 121 void *callback_arg; 122 STAILQ_ENTRY(bus_dmamap) links; 123 }; 124 125 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 126 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 127 static struct bus_dmamap nobounce_dmamap; 128 129 static void init_bounce_pages(void *dummy); 130 static int alloc_bounce_zone(bus_dma_tag_t dmat); 131 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 132 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 133 int commit); 134 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 135 vm_offset_t vaddr, bus_size_t size); 136 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 137 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 138 139 /* 140 * Return true if a match is made. 141 * 142 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 143 * 144 * If paddr is within the bounds of the dma tag then call the filter callback 145 * to check for a match, if there is no filter callback then assume a match. 146 */ 147 static __inline int 148 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 149 { 150 int retval; 151 152 retval = 0; 153 154 do { 155 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 156 || ((paddr & (dmat->alignment - 1)) != 0)) 157 && (dmat->filter == NULL 158 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 159 retval = 1; 160 161 dmat = dmat->parent; 162 } while (retval == 0 && dmat != NULL); 163 return (retval); 164 } 165 166 /* 167 * Convenience function for manipulating driver locks from busdma (during 168 * busdma_swi, for example). Drivers that don't provide their own locks 169 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 170 * non-mutex locking scheme don't have to use this at all. 171 */ 172 void 173 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 174 { 175 struct mtx *dmtx; 176 177 dmtx = (struct mtx *)arg; 178 switch (op) { 179 case BUS_DMA_LOCK: 180 mtx_lock(dmtx); 181 break; 182 case BUS_DMA_UNLOCK: 183 mtx_unlock(dmtx); 184 break; 185 default: 186 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 187 } 188 } 189 190 /* 191 * dflt_lock should never get called. It gets put into the dma tag when 192 * lockfunc == NULL, which is only valid if the maps that are associated 193 * with the tag are meant to never be defered. 194 * XXX Should have a way to identify which driver is responsible here. 195 */ 196 static void 197 dflt_lock(void *arg, bus_dma_lock_op_t op) 198 { 199 panic("driver error: busdma dflt_lock called"); 200 } 201 202 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 203 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 204 /* 205 * Allocate a device specific dma_tag. 206 */ 207 int 208 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 209 bus_size_t boundary, bus_addr_t lowaddr, 210 bus_addr_t highaddr, bus_dma_filter_t *filter, 211 void *filterarg, bus_size_t maxsize, int nsegments, 212 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 213 void *lockfuncarg, bus_dma_tag_t *dmat) 214 { 215 bus_dma_tag_t newtag; 216 int error = 0; 217 218 /* Basic sanity checking */ 219 if (boundary != 0 && boundary < maxsegsz) 220 maxsegsz = boundary; 221 222 if (maxsegsz == 0) { 223 return (EINVAL); 224 } 225 226 /* Return a NULL tag on failure */ 227 *dmat = NULL; 228 229 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 230 M_ZERO | M_NOWAIT); 231 if (newtag == NULL) { 232 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 233 __func__, newtag, 0, error); 234 return (ENOMEM); 235 } 236 237 newtag->parent = parent; 238 newtag->alignment = alignment; 239 newtag->boundary = boundary; 240 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 241 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 242 (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 || (dmat->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 } else { 437 *mapp = NULL; 438 } 439 if (error == 0) 440 dmat->map_count++; 441 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 442 __func__, dmat, dmat->flags, error); 443 return (error); 444 } 445 446 /* 447 * Destroy a handle for mapping from kva/uva/physical 448 * address space into bus device space. 449 */ 450 int 451 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 452 { 453 if (map != NULL && map != &nobounce_dmamap) { 454 if (STAILQ_FIRST(&map->bpages) != NULL) { 455 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 456 __func__, dmat, EBUSY); 457 return (EBUSY); 458 } 459 free(map, M_DEVBUF); 460 } 461 dmat->map_count--; 462 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 463 return (0); 464 } 465 466 467 /* 468 * Allocate a piece of memory that can be efficiently mapped into 469 * bus device space based on the constraints lited in the dma tag. 470 * A dmamap to for use with dmamap_load is also allocated. 471 */ 472 int 473 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 474 bus_dmamap_t *mapp) 475 { 476 int mflags; 477 478 if (flags & BUS_DMA_NOWAIT) 479 mflags = M_NOWAIT; 480 else 481 mflags = M_WAITOK; 482 if (flags & BUS_DMA_ZERO) 483 mflags |= M_ZERO; 484 485 /* If we succeed, no mapping/bouncing will be required */ 486 *mapp = NULL; 487 488 if (dmat->segments == NULL) { 489 dmat->segments = (bus_dma_segment_t *)malloc( 490 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 491 M_NOWAIT); 492 if (dmat->segments == NULL) { 493 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 494 __func__, dmat, dmat->flags, ENOMEM); 495 return (ENOMEM); 496 } 497 } 498 499 /* 500 * XXX: 501 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 502 * alignment guarantees of malloc need to be nailed down, and the 503 * code below should be rewritten to take that into account. 504 * 505 * In the meantime, we'll warn the user if malloc gets it wrong. 506 */ 507 if ((dmat->maxsize <= PAGE_SIZE) && 508 (dmat->alignment < dmat->maxsize) && 509 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 510 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 511 } else { 512 /* 513 * XXX Use Contigmalloc until it is merged into this facility 514 * and handles multi-seg allocations. Nobody is doing 515 * multi-seg allocations yet though. 516 * XXX Certain AGP hardware does. 517 */ 518 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 519 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 520 dmat->boundary); 521 } 522 if (*vaddr == NULL) { 523 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 524 __func__, dmat, dmat->flags, ENOMEM); 525 return (ENOMEM); 526 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 527 printf("bus_dmamem_alloc failed to align memory properly.\n"); 528 } 529 if (flags & BUS_DMA_NOCACHE) 530 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 531 PAT_UNCACHEABLE); 532 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 533 __func__, dmat, dmat->flags, ENOMEM); 534 return (0); 535 } 536 537 /* 538 * Free a piece of memory and it's allociated dmamap, that was allocated 539 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 540 */ 541 void 542 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 543 { 544 /* 545 * dmamem does not need to be bounced, so the map should be 546 * NULL 547 */ 548 if (map != NULL) 549 panic("bus_dmamem_free: Invalid map freed\n"); 550 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 551 if ((dmat->maxsize <= PAGE_SIZE) && 552 (dmat->alignment < dmat->maxsize) && 553 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 554 free(vaddr, M_DEVBUF); 555 else { 556 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 557 } 558 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 559 } 560 561 /* 562 * Utility function to load a linear buffer. lastaddrp holds state 563 * between invocations (for multiple-buffer loads). segp contains 564 * the starting segment on entrace, and the ending segment on exit. 565 * first indicates if this is the first invocation of this function. 566 */ 567 static __inline int 568 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 569 bus_dmamap_t map, 570 void *buf, bus_size_t buflen, 571 pmap_t pmap, 572 int flags, 573 bus_addr_t *lastaddrp, 574 bus_dma_segment_t *segs, 575 int *segp, 576 int first) 577 { 578 bus_size_t sgsize; 579 bus_addr_t curaddr, lastaddr, baddr, bmask; 580 vm_offset_t vaddr; 581 bus_addr_t paddr; 582 int seg; 583 584 if (map == NULL) 585 map = &nobounce_dmamap; 586 587 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 588 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 589 vm_offset_t vendaddr; 590 591 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 592 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 593 dmat->boundary, dmat->alignment); 594 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 595 map, &nobounce_dmamap, map->pagesneeded); 596 /* 597 * Count the number of bounce pages 598 * needed in order to complete this transfer 599 */ 600 vaddr = (vm_offset_t)buf; 601 vendaddr = (vm_offset_t)buf + buflen; 602 603 while (vaddr < vendaddr) { 604 if (pmap) 605 paddr = pmap_extract(pmap, vaddr); 606 else 607 paddr = pmap_kextract(vaddr); 608 if (run_filter(dmat, paddr) != 0) 609 map->pagesneeded++; 610 vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK)); 611 } 612 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 613 } 614 615 /* Reserve Necessary Bounce Pages */ 616 if (map->pagesneeded != 0) { 617 mtx_lock(&bounce_lock); 618 if (flags & BUS_DMA_NOWAIT) { 619 if (reserve_bounce_pages(dmat, map, 0) != 0) { 620 mtx_unlock(&bounce_lock); 621 return (ENOMEM); 622 } 623 } else { 624 if (reserve_bounce_pages(dmat, map, 1) != 0) { 625 /* Queue us for resources */ 626 map->dmat = dmat; 627 map->buf = buf; 628 map->buflen = buflen; 629 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 630 map, links); 631 mtx_unlock(&bounce_lock); 632 return (EINPROGRESS); 633 } 634 } 635 mtx_unlock(&bounce_lock); 636 } 637 638 vaddr = (vm_offset_t)buf; 639 lastaddr = *lastaddrp; 640 bmask = ~(dmat->boundary - 1); 641 642 for (seg = *segp; buflen > 0 ; ) { 643 /* 644 * Get the physical address for this segment. 645 */ 646 if (pmap) 647 curaddr = pmap_extract(pmap, vaddr); 648 else 649 curaddr = pmap_kextract(vaddr); 650 651 /* 652 * Compute the segment size, and adjust counts. 653 */ 654 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 655 if (sgsize > dmat->maxsegsz) 656 sgsize = dmat->maxsegsz; 657 if (buflen < sgsize) 658 sgsize = buflen; 659 660 /* 661 * Make sure we don't cross any boundaries. 662 */ 663 if (dmat->boundary > 0) { 664 baddr = (curaddr + dmat->boundary) & bmask; 665 if (sgsize > (baddr - curaddr)) 666 sgsize = (baddr - curaddr); 667 } 668 669 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) 670 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 671 672 /* 673 * Insert chunk into a segment, coalescing with 674 * previous segment if possible. 675 */ 676 if (first) { 677 segs[seg].ds_addr = curaddr; 678 segs[seg].ds_len = sgsize; 679 first = 0; 680 } else { 681 if (curaddr == lastaddr && 682 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 683 (dmat->boundary == 0 || 684 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 685 segs[seg].ds_len += sgsize; 686 else { 687 if (++seg >= dmat->nsegments) 688 break; 689 segs[seg].ds_addr = curaddr; 690 segs[seg].ds_len = sgsize; 691 } 692 } 693 694 lastaddr = curaddr + sgsize; 695 vaddr += sgsize; 696 buflen -= sgsize; 697 } 698 699 *segp = seg; 700 *lastaddrp = lastaddr; 701 702 /* 703 * Did we fit? 704 */ 705 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 706 } 707 708 /* 709 * Map the buffer buf into bus space using the dmamap map. 710 */ 711 int 712 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 713 bus_size_t buflen, bus_dmamap_callback_t *callback, 714 void *callback_arg, int flags) 715 { 716 bus_addr_t lastaddr = 0; 717 int error, nsegs = 0; 718 719 if (map != NULL) { 720 flags |= BUS_DMA_WAITOK; 721 map->callback = callback; 722 map->callback_arg = callback_arg; 723 } 724 725 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 726 &lastaddr, dmat->segments, &nsegs, 1); 727 728 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 729 __func__, dmat, dmat->flags, error, nsegs + 1); 730 731 if (error == EINPROGRESS) { 732 return (error); 733 } 734 735 if (error) 736 (*callback)(callback_arg, dmat->segments, 0, error); 737 else 738 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 739 740 /* 741 * Return ENOMEM to the caller so that it can pass it up the stack. 742 * This error only happens when NOWAIT is set, so deferal is disabled. 743 */ 744 if (error == ENOMEM) 745 return (error); 746 747 return (0); 748 } 749 750 751 /* 752 * Like _bus_dmamap_load(), but for mbufs. 753 */ 754 int 755 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 756 struct mbuf *m0, 757 bus_dmamap_callback2_t *callback, void *callback_arg, 758 int flags) 759 { 760 int nsegs, error; 761 762 M_ASSERTPKTHDR(m0); 763 764 flags |= BUS_DMA_NOWAIT; 765 nsegs = 0; 766 error = 0; 767 if (m0->m_pkthdr.len <= dmat->maxsize) { 768 int first = 1; 769 bus_addr_t lastaddr = 0; 770 struct mbuf *m; 771 772 for (m = m0; m != NULL && error == 0; m = m->m_next) { 773 if (m->m_len > 0) { 774 error = _bus_dmamap_load_buffer(dmat, map, 775 m->m_data, m->m_len, 776 NULL, flags, &lastaddr, 777 dmat->segments, &nsegs, first); 778 first = 0; 779 } 780 } 781 } else { 782 error = EINVAL; 783 } 784 785 if (error) { 786 /* force "no valid mappings" in callback */ 787 (*callback)(callback_arg, dmat->segments, 0, 0, error); 788 } else { 789 (*callback)(callback_arg, dmat->segments, 790 nsegs+1, m0->m_pkthdr.len, error); 791 } 792 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 793 __func__, dmat, dmat->flags, error, nsegs + 1); 794 return (error); 795 } 796 797 int 798 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 799 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 800 int flags) 801 { 802 int error; 803 804 M_ASSERTPKTHDR(m0); 805 806 flags |= BUS_DMA_NOWAIT; 807 *nsegs = 0; 808 error = 0; 809 if (m0->m_pkthdr.len <= dmat->maxsize) { 810 int first = 1; 811 bus_addr_t lastaddr = 0; 812 struct mbuf *m; 813 814 for (m = m0; m != NULL && error == 0; m = m->m_next) { 815 if (m->m_len > 0) { 816 error = _bus_dmamap_load_buffer(dmat, map, 817 m->m_data, m->m_len, 818 NULL, flags, &lastaddr, 819 segs, nsegs, first); 820 first = 0; 821 } 822 } 823 } else { 824 error = EINVAL; 825 } 826 827 /* XXX FIXME: Having to increment nsegs is really annoying */ 828 ++*nsegs; 829 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 830 __func__, dmat, dmat->flags, error, *nsegs); 831 return (error); 832 } 833 834 /* 835 * Like _bus_dmamap_load(), but for uios. 836 */ 837 int 838 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 839 struct uio *uio, 840 bus_dmamap_callback2_t *callback, void *callback_arg, 841 int flags) 842 { 843 bus_addr_t lastaddr = 0; 844 int nsegs, error, first, i; 845 bus_size_t resid; 846 struct iovec *iov; 847 pmap_t pmap; 848 849 flags |= BUS_DMA_NOWAIT; 850 resid = uio->uio_resid; 851 iov = uio->uio_iov; 852 853 if (uio->uio_segflg == UIO_USERSPACE) { 854 KASSERT(uio->uio_td != NULL, 855 ("bus_dmamap_load_uio: USERSPACE but no proc")); 856 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 857 } else 858 pmap = NULL; 859 860 nsegs = 0; 861 error = 0; 862 first = 1; 863 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 864 /* 865 * Now at the first iovec to load. Load each iovec 866 * until we have exhausted the residual count. 867 */ 868 bus_size_t minlen = 869 resid < iov[i].iov_len ? resid : iov[i].iov_len; 870 caddr_t addr = (caddr_t) iov[i].iov_base; 871 872 if (minlen > 0) { 873 error = _bus_dmamap_load_buffer(dmat, map, 874 addr, minlen, pmap, flags, &lastaddr, 875 dmat->segments, &nsegs, first); 876 first = 0; 877 878 resid -= minlen; 879 } 880 } 881 882 if (error) { 883 /* force "no valid mappings" in callback */ 884 (*callback)(callback_arg, dmat->segments, 0, 0, error); 885 } else { 886 (*callback)(callback_arg, dmat->segments, 887 nsegs+1, uio->uio_resid, error); 888 } 889 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 890 __func__, dmat, dmat->flags, error, nsegs + 1); 891 return (error); 892 } 893 894 /* 895 * Release the mapping held by map. 896 */ 897 void 898 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 899 { 900 struct bounce_page *bpage; 901 902 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 903 STAILQ_REMOVE_HEAD(&map->bpages, links); 904 free_bounce_page(dmat, bpage); 905 } 906 } 907 908 void 909 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 910 { 911 struct bounce_page *bpage; 912 913 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 914 /* 915 * Handle data bouncing. We might also 916 * want to add support for invalidating 917 * the caches on broken hardware 918 */ 919 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 920 "performing bounce", __func__, op, dmat, dmat->flags); 921 922 if (op & BUS_DMASYNC_PREWRITE) { 923 while (bpage != NULL) { 924 bcopy((void *)bpage->datavaddr, 925 (void *)bpage->vaddr, 926 bpage->datacount); 927 bpage = STAILQ_NEXT(bpage, links); 928 } 929 dmat->bounce_zone->total_bounced++; 930 } 931 932 if (op & BUS_DMASYNC_POSTREAD) { 933 while (bpage != NULL) { 934 bcopy((void *)bpage->vaddr, 935 (void *)bpage->datavaddr, 936 bpage->datacount); 937 bpage = STAILQ_NEXT(bpage, links); 938 } 939 dmat->bounce_zone->total_bounced++; 940 } 941 } 942 } 943 944 static void 945 init_bounce_pages(void *dummy __unused) 946 { 947 948 total_bpages = 0; 949 STAILQ_INIT(&bounce_zone_list); 950 STAILQ_INIT(&bounce_map_waitinglist); 951 STAILQ_INIT(&bounce_map_callbacklist); 952 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 953 } 954 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 955 956 static struct sysctl_ctx_list * 957 busdma_sysctl_tree(struct bounce_zone *bz) 958 { 959 return (&bz->sysctl_tree); 960 } 961 962 static struct sysctl_oid * 963 busdma_sysctl_tree_top(struct bounce_zone *bz) 964 { 965 return (bz->sysctl_tree_top); 966 } 967 968 static int 969 alloc_bounce_zone(bus_dma_tag_t dmat) 970 { 971 struct bounce_zone *bz; 972 973 /* Check to see if we already have a suitable zone */ 974 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 975 if ((dmat->alignment <= bz->alignment) 976 && (dmat->lowaddr >= bz->lowaddr)) { 977 dmat->bounce_zone = bz; 978 return (0); 979 } 980 } 981 982 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 983 M_NOWAIT | M_ZERO)) == NULL) 984 return (ENOMEM); 985 986 STAILQ_INIT(&bz->bounce_page_list); 987 bz->free_bpages = 0; 988 bz->reserved_bpages = 0; 989 bz->active_bpages = 0; 990 bz->lowaddr = dmat->lowaddr; 991 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 992 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 993 busdma_zonecount++; 994 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 995 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 996 dmat->bounce_zone = bz; 997 998 sysctl_ctx_init(&bz->sysctl_tree); 999 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1000 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1001 CTLFLAG_RD, 0, ""); 1002 if (bz->sysctl_tree_top == NULL) { 1003 sysctl_ctx_free(&bz->sysctl_tree); 1004 return (0); /* XXX error code? */ 1005 } 1006 1007 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1008 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1009 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1010 "Total bounce pages"); 1011 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1012 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1013 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1014 "Free bounce pages"); 1015 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1016 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1017 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1018 "Reserved bounce pages"); 1019 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1020 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1021 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1022 "Active bounce pages"); 1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1025 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1026 "Total bounce requests"); 1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1029 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1030 "Total bounce requests that were deferred"); 1031 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1032 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1033 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1034 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1035 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1036 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1037 1038 return (0); 1039 } 1040 1041 static int 1042 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1043 { 1044 struct bounce_zone *bz; 1045 int count; 1046 1047 bz = dmat->bounce_zone; 1048 count = 0; 1049 while (numpages > 0) { 1050 struct bounce_page *bpage; 1051 1052 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1053 M_NOWAIT | M_ZERO); 1054 1055 if (bpage == NULL) 1056 break; 1057 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1058 M_NOWAIT, 0ul, 1059 bz->lowaddr, 1060 PAGE_SIZE, 1061 0); 1062 if (bpage->vaddr == 0) { 1063 free(bpage, M_DEVBUF); 1064 break; 1065 } 1066 bpage->busaddr = pmap_kextract(bpage->vaddr); 1067 mtx_lock(&bounce_lock); 1068 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1069 total_bpages++; 1070 bz->total_bpages++; 1071 bz->free_bpages++; 1072 mtx_unlock(&bounce_lock); 1073 count++; 1074 numpages--; 1075 } 1076 return (count); 1077 } 1078 1079 static int 1080 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1081 { 1082 struct bounce_zone *bz; 1083 int pages; 1084 1085 mtx_assert(&bounce_lock, MA_OWNED); 1086 bz = dmat->bounce_zone; 1087 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1088 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1089 return (map->pagesneeded - (map->pagesreserved + pages)); 1090 bz->free_bpages -= pages; 1091 bz->reserved_bpages += pages; 1092 map->pagesreserved += pages; 1093 pages = map->pagesneeded - map->pagesreserved; 1094 1095 return (pages); 1096 } 1097 1098 static bus_addr_t 1099 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1100 bus_size_t size) 1101 { 1102 struct bounce_zone *bz; 1103 struct bounce_page *bpage; 1104 1105 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1106 KASSERT(map != NULL && map != &nobounce_dmamap, 1107 ("add_bounce_page: bad map %p", map)); 1108 1109 bz = dmat->bounce_zone; 1110 if (map->pagesneeded == 0) 1111 panic("add_bounce_page: map doesn't need any pages"); 1112 map->pagesneeded--; 1113 1114 if (map->pagesreserved == 0) 1115 panic("add_bounce_page: map doesn't need any pages"); 1116 map->pagesreserved--; 1117 1118 mtx_lock(&bounce_lock); 1119 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1120 if (bpage == NULL) 1121 panic("add_bounce_page: free page list is empty"); 1122 1123 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1124 bz->reserved_bpages--; 1125 bz->active_bpages++; 1126 mtx_unlock(&bounce_lock); 1127 1128 bpage->datavaddr = vaddr; 1129 bpage->datacount = size; 1130 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1131 return (bpage->busaddr); 1132 } 1133 1134 static void 1135 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1136 { 1137 struct bus_dmamap *map; 1138 struct bounce_zone *bz; 1139 1140 bz = dmat->bounce_zone; 1141 bpage->datavaddr = 0; 1142 bpage->datacount = 0; 1143 1144 mtx_lock(&bounce_lock); 1145 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1146 bz->free_bpages++; 1147 bz->active_bpages--; 1148 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1149 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1150 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1151 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1152 map, links); 1153 busdma_swi_pending = 1; 1154 bz->total_deferred++; 1155 swi_sched(vm_ih, 0); 1156 } 1157 } 1158 mtx_unlock(&bounce_lock); 1159 } 1160 1161 void 1162 busdma_swi(void) 1163 { 1164 bus_dma_tag_t dmat; 1165 struct bus_dmamap *map; 1166 1167 mtx_lock(&bounce_lock); 1168 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1169 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1170 mtx_unlock(&bounce_lock); 1171 dmat = map->dmat; 1172 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1173 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1174 map->callback, map->callback_arg, /*flags*/0); 1175 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1176 mtx_lock(&bounce_lock); 1177 } 1178 mtx_unlock(&bounce_lock); 1179 }
Cache object: b5117226f282474dae42aaa85c0f8cd2
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