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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/6.3/sys/amd64/amd64/busdma_machdep.c 173886 2007-11-24 19:45:58Z cvs2svn $"); 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_size_t boundary; 98 bus_addr_t lowaddr; 99 char zoneid[8]; 100 char lowaddrid[20]; 101 struct sysctl_ctx_list sysctl_tree; 102 struct sysctl_oid *sysctl_tree_top; 103 }; 104 105 static struct mtx bounce_lock; 106 static int total_bpages; 107 static int busdma_zonecount; 108 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 109 110 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 111 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 112 "Total bounce pages"); 113 114 struct bus_dmamap { 115 struct bp_list bpages; 116 int pagesneeded; 117 int pagesreserved; 118 bus_dma_tag_t dmat; 119 void *buf; /* unmapped buffer pointer */ 120 bus_size_t buflen; /* unmapped buffer length */ 121 bus_dmamap_callback_t *callback; 122 void *callback_arg; 123 STAILQ_ENTRY(bus_dmamap) links; 124 }; 125 126 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 128 static struct bus_dmamap nobounce_dmamap; 129 130 static void init_bounce_pages(void *dummy); 131 static int alloc_bounce_zone(bus_dma_tag_t dmat); 132 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 133 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 134 int commit); 135 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 136 vm_offset_t vaddr, bus_size_t size); 137 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 138 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 139 140 /* 141 * Return true if a match is made. 142 * 143 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 144 * 145 * If paddr is within the bounds of the dma tag then call the filter callback 146 * to check for a match, if there is no filter callback then assume a match. 147 */ 148 static __inline int 149 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 150 { 151 int retval; 152 153 retval = 0; 154 155 do { 156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 157 || ((paddr & (dmat->alignment - 1)) != 0)) 158 && (dmat->filter == NULL 159 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 160 retval = 1; 161 162 dmat = dmat->parent; 163 } while (retval == 0 && dmat != NULL); 164 return (retval); 165 } 166 167 /* 168 * Convenience function for manipulating driver locks from busdma (during 169 * busdma_swi, for example). Drivers that don't provide their own locks 170 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 171 * non-mutex locking scheme don't have to use this at all. 172 */ 173 void 174 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 175 { 176 struct mtx *dmtx; 177 178 dmtx = (struct mtx *)arg; 179 switch (op) { 180 case BUS_DMA_LOCK: 181 mtx_lock(dmtx); 182 break; 183 case BUS_DMA_UNLOCK: 184 mtx_unlock(dmtx); 185 break; 186 default: 187 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 188 } 189 } 190 191 /* 192 * dflt_lock should never get called. It gets put into the dma tag when 193 * lockfunc == NULL, which is only valid if the maps that are associated 194 * with the tag are meant to never be defered. 195 * XXX Should have a way to identify which driver is responsible here. 196 */ 197 static void 198 dflt_lock(void *arg, bus_dma_lock_op_t op) 199 { 200 panic("driver error: busdma dflt_lock called"); 201 } 202 203 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 204 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 205 /* 206 * Allocate a device specific dma_tag. 207 */ 208 int 209 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 210 bus_size_t boundary, bus_addr_t lowaddr, 211 bus_addr_t highaddr, bus_dma_filter_t *filter, 212 void *filterarg, bus_size_t maxsize, int nsegments, 213 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 214 void *lockfuncarg, bus_dma_tag_t *dmat) 215 { 216 bus_dma_tag_t newtag; 217 int error = 0; 218 219 /* Basic sanity checking */ 220 if (boundary != 0 && boundary < maxsegsz) 221 maxsegsz = boundary; 222 223 /* Return a NULL tag on failure */ 224 *dmat = NULL; 225 226 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 227 M_ZERO | M_NOWAIT); 228 if (newtag == NULL) { 229 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 230 __func__, newtag, 0, error); 231 return (ENOMEM); 232 } 233 234 newtag->parent = parent; 235 newtag->alignment = alignment; 236 newtag->boundary = boundary; 237 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 238 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 239 (PAGE_SIZE - 1); 240 newtag->filter = filter; 241 newtag->filterarg = filterarg; 242 newtag->maxsize = maxsize; 243 newtag->nsegments = nsegments; 244 newtag->maxsegsz = maxsegsz; 245 newtag->flags = flags; 246 newtag->ref_count = 1; /* Count ourself */ 247 newtag->map_count = 0; 248 if (lockfunc != NULL) { 249 newtag->lockfunc = lockfunc; 250 newtag->lockfuncarg = lockfuncarg; 251 } else { 252 newtag->lockfunc = dflt_lock; 253 newtag->lockfuncarg = NULL; 254 } 255 newtag->segments = NULL; 256 257 /* Take into account any restrictions imposed by our parent tag */ 258 if (parent != NULL) { 259 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 260 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 261 if (newtag->boundary == 0) 262 newtag->boundary = parent->boundary; 263 else if (parent->boundary != 0) 264 newtag->boundary = MIN(parent->boundary, 265 newtag->boundary); 266 if (newtag->filter == NULL) { 267 /* 268 * Short circuit looking at our parent directly 269 * since we have encapsulated all of its information 270 */ 271 newtag->filter = parent->filter; 272 newtag->filterarg = parent->filterarg; 273 newtag->parent = parent->parent; 274 } 275 if (newtag->parent != NULL) 276 atomic_add_int(&parent->ref_count, 1); 277 } 278 279 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 280 || newtag->alignment > 1) 281 newtag->flags |= BUS_DMA_COULD_BOUNCE; 282 283 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 284 (flags & BUS_DMA_ALLOCNOW) != 0) { 285 struct bounce_zone *bz; 286 287 /* Must bounce */ 288 289 if ((error = alloc_bounce_zone(newtag)) != 0) { 290 free(newtag, M_DEVBUF); 291 return (error); 292 } 293 bz = newtag->bounce_zone; 294 295 if (ptoa(bz->total_bpages) < maxsize) { 296 int pages; 297 298 pages = atop(maxsize) - bz->total_bpages; 299 300 /* Add pages to our bounce pool */ 301 if (alloc_bounce_pages(newtag, pages) < pages) 302 error = ENOMEM; 303 } 304 /* Performed initial allocation */ 305 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 306 } 307 308 if (error != 0) { 309 free(newtag, M_DEVBUF); 310 } else { 311 *dmat = newtag; 312 } 313 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 314 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 315 return (error); 316 } 317 318 int 319 bus_dma_tag_destroy(bus_dma_tag_t dmat) 320 { 321 bus_dma_tag_t dmat_copy; 322 int error; 323 324 error = 0; 325 dmat_copy = dmat; 326 327 if (dmat != NULL) { 328 329 if (dmat->map_count != 0) { 330 error = EBUSY; 331 goto out; 332 } 333 334 while (dmat != NULL) { 335 bus_dma_tag_t parent; 336 337 parent = dmat->parent; 338 atomic_subtract_int(&dmat->ref_count, 1); 339 if (dmat->ref_count == 0) { 340 if (dmat->segments != NULL) 341 free(dmat->segments, M_DEVBUF); 342 free(dmat, M_DEVBUF); 343 /* 344 * Last reference count, so 345 * release our reference 346 * count on our parent. 347 */ 348 dmat = parent; 349 } else 350 dmat = NULL; 351 } 352 } 353 out: 354 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 355 return (error); 356 } 357 358 /* 359 * Allocate a handle for mapping from kva/uva/physical 360 * address space into bus device space. 361 */ 362 int 363 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 364 { 365 int error; 366 367 error = 0; 368 369 if (dmat->segments == NULL) { 370 dmat->segments = (bus_dma_segment_t *)malloc( 371 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 372 M_NOWAIT); 373 if (dmat->segments == NULL) { 374 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 375 __func__, dmat, ENOMEM); 376 return (ENOMEM); 377 } 378 } 379 380 /* 381 * Bouncing might be required if the driver asks for an active 382 * exclusion region, a data alignment that is stricter than 1, and/or 383 * an active address boundary. 384 */ 385 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 386 387 /* Must bounce */ 388 struct bounce_zone *bz; 389 int maxpages; 390 391 if (dmat->bounce_zone == NULL) { 392 if ((error = alloc_bounce_zone(dmat)) != 0) 393 return (error); 394 } 395 bz = dmat->bounce_zone; 396 397 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 398 M_NOWAIT | M_ZERO); 399 if (*mapp == NULL) { 400 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 401 __func__, dmat, ENOMEM); 402 return (ENOMEM); 403 } 404 405 /* Initialize the new map */ 406 STAILQ_INIT(&((*mapp)->bpages)); 407 408 /* 409 * Attempt to add pages to our pool on a per-instance 410 * basis up to a sane limit. 411 */ 412 if (dmat->alignment > 1) 413 maxpages = MAX_BPAGES; 414 else 415 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 416 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 417 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 418 int pages; 419 420 pages = MAX(atop(dmat->maxsize), 1); 421 pages = MIN(maxpages - bz->total_bpages, pages); 422 pages = MAX(pages, 1); 423 if (alloc_bounce_pages(dmat, pages) < pages) 424 error = ENOMEM; 425 426 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 427 if (error == 0) 428 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 429 } else { 430 error = 0; 431 } 432 } 433 } else { 434 *mapp = NULL; 435 } 436 if (error == 0) 437 dmat->map_count++; 438 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 439 __func__, dmat, dmat->flags, error); 440 return (error); 441 } 442 443 /* 444 * Destroy a handle for mapping from kva/uva/physical 445 * address space into bus device space. 446 */ 447 int 448 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 449 { 450 if (map != NULL && map != &nobounce_dmamap) { 451 if (STAILQ_FIRST(&map->bpages) != NULL) { 452 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 453 __func__, dmat, EBUSY); 454 return (EBUSY); 455 } 456 free(map, M_DEVBUF); 457 } 458 dmat->map_count--; 459 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 460 return (0); 461 } 462 463 464 /* 465 * Allocate a piece of memory that can be efficiently mapped into 466 * bus device space based on the constraints lited in the dma tag. 467 * A dmamap to for use with dmamap_load is also allocated. 468 */ 469 int 470 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 471 bus_dmamap_t *mapp) 472 { 473 int mflags; 474 475 if (flags & BUS_DMA_NOWAIT) 476 mflags = M_NOWAIT; 477 else 478 mflags = M_WAITOK; 479 if (flags & BUS_DMA_ZERO) 480 mflags |= M_ZERO; 481 482 /* If we succeed, no mapping/bouncing will be required */ 483 *mapp = NULL; 484 485 if (dmat->segments == NULL) { 486 dmat->segments = (bus_dma_segment_t *)malloc( 487 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 488 M_NOWAIT); 489 if (dmat->segments == NULL) { 490 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 491 __func__, dmat, dmat->flags, ENOMEM); 492 return (ENOMEM); 493 } 494 } 495 496 /* 497 * XXX: 498 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 499 * alignment guarantees of malloc need to be nailed down, and the 500 * code below should be rewritten to take that into account. 501 * 502 * In the meantime, we'll warn the user if malloc gets it wrong. 503 */ 504 if ((dmat->maxsize <= PAGE_SIZE) && 505 (dmat->alignment < dmat->maxsize) && 506 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 507 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 508 } else { 509 /* 510 * XXX Use Contigmalloc until it is merged into this facility 511 * and handles multi-seg allocations. Nobody is doing 512 * multi-seg allocations yet though. 513 * XXX Certain AGP hardware does. 514 */ 515 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 516 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 517 dmat->boundary); 518 } 519 if (*vaddr == NULL) { 520 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 521 __func__, dmat, dmat->flags, ENOMEM); 522 return (ENOMEM); 523 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 524 printf("bus_dmamem_alloc failed to align memory properly.\n"); 525 } 526 if (flags & BUS_DMA_NOCACHE) 527 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 528 PAT_UNCACHEABLE); 529 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 530 __func__, dmat, dmat->flags, ENOMEM); 531 return (0); 532 } 533 534 /* 535 * Free a piece of memory and it's allociated dmamap, that was allocated 536 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 537 */ 538 void 539 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 540 { 541 /* 542 * dmamem does not need to be bounced, so the map should be 543 * NULL 544 */ 545 if (map != NULL) 546 panic("bus_dmamem_free: Invalid map freed\n"); 547 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 548 if ((dmat->maxsize <= PAGE_SIZE) && 549 (dmat->alignment < dmat->maxsize) && 550 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 551 free(vaddr, M_DEVBUF); 552 else { 553 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 554 } 555 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 556 } 557 558 /* 559 * Utility function to load a linear buffer. lastaddrp holds state 560 * between invocations (for multiple-buffer loads). segp contains 561 * the starting segment on entrace, and the ending segment on exit. 562 * first indicates if this is the first invocation of this function. 563 */ 564 static __inline int 565 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 566 bus_dmamap_t map, 567 void *buf, bus_size_t buflen, 568 pmap_t pmap, 569 int flags, 570 bus_addr_t *lastaddrp, 571 bus_dma_segment_t *segs, 572 int *segp, 573 int first) 574 { 575 bus_size_t sgsize; 576 bus_addr_t curaddr, lastaddr, baddr, bmask; 577 vm_offset_t vaddr; 578 bus_addr_t paddr; 579 int needbounce = 0; 580 int seg; 581 582 if (map == NULL) 583 map = &nobounce_dmamap; 584 585 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 586 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 587 vm_offset_t vendaddr; 588 589 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 590 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 591 dmat->boundary, dmat->alignment); 592 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 593 map, &nobounce_dmamap, map->pagesneeded); 594 /* 595 * Count the number of bounce pages 596 * needed in order to complete this transfer 597 */ 598 vaddr = trunc_page((vm_offset_t)buf); 599 vendaddr = (vm_offset_t)buf + buflen; 600 601 while (vaddr < vendaddr) { 602 paddr = pmap_kextract(vaddr); 603 if (run_filter(dmat, paddr) != 0) { 604 needbounce = 1; 605 map->pagesneeded++; 606 } 607 vaddr += PAGE_SIZE; 608 } 609 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 610 } 611 612 /* Reserve Necessary Bounce Pages */ 613 if (map->pagesneeded != 0) { 614 mtx_lock(&bounce_lock); 615 if (flags & BUS_DMA_NOWAIT) { 616 if (reserve_bounce_pages(dmat, map, 0) != 0) { 617 mtx_unlock(&bounce_lock); 618 return (ENOMEM); 619 } 620 } else { 621 if (reserve_bounce_pages(dmat, map, 1) != 0) { 622 /* Queue us for resources */ 623 map->dmat = dmat; 624 map->buf = buf; 625 map->buflen = buflen; 626 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 627 map, links); 628 mtx_unlock(&bounce_lock); 629 return (EINPROGRESS); 630 } 631 } 632 mtx_unlock(&bounce_lock); 633 } 634 635 vaddr = (vm_offset_t)buf; 636 lastaddr = *lastaddrp; 637 bmask = ~(dmat->boundary - 1); 638 639 for (seg = *segp; buflen > 0 ; ) { 640 /* 641 * Get the physical address for this segment. 642 */ 643 if (pmap) 644 curaddr = pmap_extract(pmap, vaddr); 645 else 646 curaddr = pmap_kextract(vaddr); 647 648 /* 649 * Compute the segment size, and adjust counts. 650 */ 651 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 652 if (buflen < sgsize) 653 sgsize = buflen; 654 655 /* 656 * Make sure we don't cross any boundaries. 657 */ 658 if (dmat->boundary > 0) { 659 baddr = (curaddr + dmat->boundary) & bmask; 660 if (sgsize > (baddr - curaddr)) 661 sgsize = (baddr - curaddr); 662 } 663 664 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) 665 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 666 667 /* 668 * Insert chunk into a segment, coalescing with 669 * previous segment if possible. 670 */ 671 if (first) { 672 segs[seg].ds_addr = curaddr; 673 segs[seg].ds_len = sgsize; 674 first = 0; 675 } else { 676 if (needbounce == 0 && curaddr == lastaddr && 677 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 678 (dmat->boundary == 0 || 679 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 680 segs[seg].ds_len += sgsize; 681 else { 682 if (++seg >= dmat->nsegments) 683 break; 684 segs[seg].ds_addr = curaddr; 685 segs[seg].ds_len = sgsize; 686 } 687 } 688 689 lastaddr = curaddr + sgsize; 690 vaddr += sgsize; 691 buflen -= sgsize; 692 } 693 694 *segp = seg; 695 *lastaddrp = lastaddr; 696 697 /* 698 * Did we fit? 699 */ 700 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 701 } 702 703 /* 704 * Map the buffer buf into bus space using the dmamap map. 705 */ 706 int 707 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 708 bus_size_t buflen, bus_dmamap_callback_t *callback, 709 void *callback_arg, int flags) 710 { 711 bus_addr_t lastaddr = 0; 712 int error, nsegs = 0; 713 714 if (map != NULL) { 715 flags |= BUS_DMA_WAITOK; 716 map->callback = callback; 717 map->callback_arg = callback_arg; 718 } 719 720 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 721 &lastaddr, dmat->segments, &nsegs, 1); 722 723 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 724 __func__, dmat, dmat->flags, error, nsegs + 1); 725 726 if (error == EINPROGRESS) { 727 return (error); 728 } 729 730 if (error) 731 (*callback)(callback_arg, dmat->segments, 0, error); 732 else 733 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 734 735 /* 736 * Return ENOMEM to the caller so that it can pass it up the stack. 737 * This error only happens when NOWAIT is set, so deferal is disabled. 738 */ 739 if (error == ENOMEM) 740 return (error); 741 742 return (0); 743 } 744 745 746 /* 747 * Like _bus_dmamap_load(), but for mbufs. 748 */ 749 int 750 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 751 struct mbuf *m0, 752 bus_dmamap_callback2_t *callback, void *callback_arg, 753 int flags) 754 { 755 int nsegs, error; 756 757 M_ASSERTPKTHDR(m0); 758 759 flags |= BUS_DMA_NOWAIT; 760 nsegs = 0; 761 error = 0; 762 if (m0->m_pkthdr.len <= dmat->maxsize) { 763 int first = 1; 764 bus_addr_t lastaddr = 0; 765 struct mbuf *m; 766 767 for (m = m0; m != NULL && error == 0; m = m->m_next) { 768 if (m->m_len > 0) { 769 error = _bus_dmamap_load_buffer(dmat, map, 770 m->m_data, m->m_len, 771 NULL, flags, &lastaddr, 772 dmat->segments, &nsegs, first); 773 first = 0; 774 } 775 } 776 } else { 777 error = EINVAL; 778 } 779 780 if (error) { 781 /* force "no valid mappings" in callback */ 782 (*callback)(callback_arg, dmat->segments, 0, 0, error); 783 } else { 784 (*callback)(callback_arg, dmat->segments, 785 nsegs+1, m0->m_pkthdr.len, error); 786 } 787 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 788 __func__, dmat, dmat->flags, error, nsegs + 1); 789 return (error); 790 } 791 792 int 793 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 794 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 795 int flags) 796 { 797 int error; 798 799 M_ASSERTPKTHDR(m0); 800 801 flags |= BUS_DMA_NOWAIT; 802 *nsegs = 0; 803 error = 0; 804 if (m0->m_pkthdr.len <= dmat->maxsize) { 805 int first = 1; 806 bus_addr_t lastaddr = 0; 807 struct mbuf *m; 808 809 for (m = m0; m != NULL && error == 0; m = m->m_next) { 810 if (m->m_len > 0) { 811 error = _bus_dmamap_load_buffer(dmat, map, 812 m->m_data, m->m_len, 813 NULL, flags, &lastaddr, 814 segs, nsegs, first); 815 first = 0; 816 } 817 } 818 } else { 819 error = EINVAL; 820 } 821 822 /* XXX FIXME: Having to increment nsegs is really annoying */ 823 ++*nsegs; 824 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 825 __func__, dmat, dmat->flags, error, *nsegs); 826 return (error); 827 } 828 829 /* 830 * Like _bus_dmamap_load(), but for uios. 831 */ 832 int 833 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 834 struct uio *uio, 835 bus_dmamap_callback2_t *callback, void *callback_arg, 836 int flags) 837 { 838 bus_addr_t lastaddr; 839 int nsegs, error, first, i; 840 bus_size_t resid; 841 struct iovec *iov; 842 pmap_t pmap; 843 844 flags |= BUS_DMA_NOWAIT; 845 resid = uio->uio_resid; 846 iov = uio->uio_iov; 847 848 if (uio->uio_segflg == UIO_USERSPACE) { 849 KASSERT(uio->uio_td != NULL, 850 ("bus_dmamap_load_uio: USERSPACE but no proc")); 851 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 852 } else 853 pmap = NULL; 854 855 nsegs = 0; 856 error = 0; 857 first = 1; 858 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 859 /* 860 * Now at the first iovec to load. Load each iovec 861 * until we have exhausted the residual count. 862 */ 863 bus_size_t minlen = 864 resid < iov[i].iov_len ? resid : iov[i].iov_len; 865 caddr_t addr = (caddr_t) iov[i].iov_base; 866 867 if (minlen > 0) { 868 error = _bus_dmamap_load_buffer(dmat, map, 869 addr, minlen, pmap, flags, &lastaddr, 870 dmat->segments, &nsegs, first); 871 first = 0; 872 873 resid -= minlen; 874 } 875 } 876 877 if (error) { 878 /* force "no valid mappings" in callback */ 879 (*callback)(callback_arg, dmat->segments, 0, 0, error); 880 } else { 881 (*callback)(callback_arg, dmat->segments, 882 nsegs+1, uio->uio_resid, error); 883 } 884 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 885 __func__, dmat, dmat->flags, error, nsegs + 1); 886 return (error); 887 } 888 889 /* 890 * Release the mapping held by map. 891 */ 892 void 893 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 894 { 895 struct bounce_page *bpage; 896 897 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 898 STAILQ_REMOVE_HEAD(&map->bpages, links); 899 free_bounce_page(dmat, bpage); 900 } 901 } 902 903 void 904 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 905 { 906 struct bounce_page *bpage; 907 908 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 909 /* 910 * Handle data bouncing. We might also 911 * want to add support for invalidating 912 * the caches on broken hardware 913 */ 914 dmat->bounce_zone->total_bounced++; 915 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 916 "performing bounce", __func__, op, dmat, dmat->flags); 917 918 if (op & BUS_DMASYNC_PREWRITE) { 919 while (bpage != NULL) { 920 bcopy((void *)bpage->datavaddr, 921 (void *)bpage->vaddr, 922 bpage->datacount); 923 bpage = STAILQ_NEXT(bpage, links); 924 } 925 } 926 927 if (op & BUS_DMASYNC_POSTREAD) { 928 while (bpage != NULL) { 929 bcopy((void *)bpage->vaddr, 930 (void *)bpage->datavaddr, 931 bpage->datacount); 932 bpage = STAILQ_NEXT(bpage, links); 933 } 934 } 935 } 936 } 937 938 static void 939 init_bounce_pages(void *dummy __unused) 940 { 941 942 total_bpages = 0; 943 STAILQ_INIT(&bounce_zone_list); 944 STAILQ_INIT(&bounce_map_waitinglist); 945 STAILQ_INIT(&bounce_map_callbacklist); 946 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 947 } 948 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 949 950 static struct sysctl_ctx_list * 951 busdma_sysctl_tree(struct bounce_zone *bz) 952 { 953 return (&bz->sysctl_tree); 954 } 955 956 static struct sysctl_oid * 957 busdma_sysctl_tree_top(struct bounce_zone *bz) 958 { 959 return (bz->sysctl_tree_top); 960 } 961 962 static int 963 alloc_bounce_zone(bus_dma_tag_t dmat) 964 { 965 struct bounce_zone *bz; 966 967 /* Check to see if we already have a suitable zone */ 968 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 969 if ((dmat->alignment <= bz->alignment) 970 && (dmat->boundary <= bz->boundary) 971 && (dmat->lowaddr >= bz->lowaddr)) { 972 dmat->bounce_zone = bz; 973 return (0); 974 } 975 } 976 977 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 978 M_NOWAIT | M_ZERO)) == NULL) 979 return (ENOMEM); 980 981 STAILQ_INIT(&bz->bounce_page_list); 982 bz->free_bpages = 0; 983 bz->reserved_bpages = 0; 984 bz->active_bpages = 0; 985 bz->lowaddr = dmat->lowaddr; 986 bz->alignment = dmat->alignment; 987 bz->boundary = dmat->boundary; 988 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 989 busdma_zonecount++; 990 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 991 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 992 dmat->bounce_zone = bz; 993 994 sysctl_ctx_init(&bz->sysctl_tree); 995 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 996 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 997 CTLFLAG_RD, 0, ""); 998 if (bz->sysctl_tree_top == NULL) { 999 sysctl_ctx_free(&bz->sysctl_tree); 1000 return (0); /* XXX error code? */ 1001 } 1002 1003 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1004 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1005 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1006 "Total bounce pages"); 1007 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1008 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1009 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1010 "Free bounce pages"); 1011 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1012 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1013 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1014 "Reserved bounce pages"); 1015 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1016 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1017 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1018 "Active bounce pages"); 1019 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1020 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1021 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1022 "Total bounce requests"); 1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1025 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1026 "Total bounce requests that were deferred"); 1027 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1029 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1032 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1033 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1034 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1035 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 1036 1037 return (0); 1038 } 1039 1040 static int 1041 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1042 { 1043 struct bounce_zone *bz; 1044 int count; 1045 1046 bz = dmat->bounce_zone; 1047 count = 0; 1048 while (numpages > 0) { 1049 struct bounce_page *bpage; 1050 1051 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1052 M_NOWAIT | M_ZERO); 1053 1054 if (bpage == NULL) 1055 break; 1056 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1057 M_NOWAIT, 0ul, 1058 bz->lowaddr, 1059 PAGE_SIZE, 1060 bz->boundary); 1061 if (bpage->vaddr == 0) { 1062 free(bpage, M_DEVBUF); 1063 break; 1064 } 1065 bpage->busaddr = pmap_kextract(bpage->vaddr); 1066 mtx_lock(&bounce_lock); 1067 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1068 total_bpages++; 1069 bz->total_bpages++; 1070 bz->free_bpages++; 1071 mtx_unlock(&bounce_lock); 1072 count++; 1073 numpages--; 1074 } 1075 return (count); 1076 } 1077 1078 static int 1079 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1080 { 1081 struct bounce_zone *bz; 1082 int pages; 1083 1084 mtx_assert(&bounce_lock, MA_OWNED); 1085 bz = dmat->bounce_zone; 1086 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1087 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1088 return (map->pagesneeded - (map->pagesreserved + pages)); 1089 bz->free_bpages -= pages; 1090 bz->reserved_bpages += pages; 1091 map->pagesreserved += pages; 1092 pages = map->pagesneeded - map->pagesreserved; 1093 1094 return (pages); 1095 } 1096 1097 static bus_addr_t 1098 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1099 bus_size_t size) 1100 { 1101 struct bounce_zone *bz; 1102 struct bounce_page *bpage; 1103 1104 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1105 KASSERT(map != NULL && map != &nobounce_dmamap, 1106 ("add_bounce_page: bad map %p", map)); 1107 1108 bz = dmat->bounce_zone; 1109 if (map->pagesneeded == 0) 1110 panic("add_bounce_page: map doesn't need any pages"); 1111 map->pagesneeded--; 1112 1113 if (map->pagesreserved == 0) 1114 panic("add_bounce_page: map doesn't need any pages"); 1115 map->pagesreserved--; 1116 1117 mtx_lock(&bounce_lock); 1118 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1119 if (bpage == NULL) 1120 panic("add_bounce_page: free page list is empty"); 1121 1122 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1123 bz->reserved_bpages--; 1124 bz->active_bpages++; 1125 mtx_unlock(&bounce_lock); 1126 1127 bpage->datavaddr = vaddr; 1128 bpage->datacount = size; 1129 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1130 return (bpage->busaddr); 1131 } 1132 1133 static void 1134 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1135 { 1136 struct bus_dmamap *map; 1137 struct bounce_zone *bz; 1138 1139 bz = dmat->bounce_zone; 1140 bpage->datavaddr = 0; 1141 bpage->datacount = 0; 1142 1143 mtx_lock(&bounce_lock); 1144 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1145 bz->free_bpages++; 1146 bz->active_bpages--; 1147 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1148 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1149 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1150 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1151 map, links); 1152 busdma_swi_pending = 1; 1153 bz->total_deferred++; 1154 swi_sched(vm_ih, 0); 1155 } 1156 } 1157 mtx_unlock(&bounce_lock); 1158 } 1159 1160 void 1161 busdma_swi(void) 1162 { 1163 bus_dma_tag_t dmat; 1164 struct bus_dmamap *map; 1165 1166 mtx_lock(&bounce_lock); 1167 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1168 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1169 mtx_unlock(&bounce_lock); 1170 dmat = map->dmat; 1171 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1172 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1173 map->callback, map->callback_arg, /*flags*/0); 1174 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1175 mtx_lock(&bounce_lock); 1176 } 1177 mtx_unlock(&bounce_lock); 1178 }
Cache object: 34ebb15bd38d3e65c61fb55d84af7683
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