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sys/amd64/amd64/busdma_machdep.c
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1 /*- 2 * Copyright (c) 1997, 1998 Justin T. Gibbs. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions, and the following disclaimer, 10 * without modification, immediately at the beginning of the file. 11 * 2. The name of the author may not be used to endorse or promote products 12 * derived from this software without specific prior written permission. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 18 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD: releng/8.4/sys/amd64/amd64/busdma_machdep.c 232354 2012-03-01 19:43:28Z emaste $"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/malloc.h> 33 #include <sys/bus.h> 34 #include <sys/interrupt.h> 35 #include <sys/kernel.h> 36 #include <sys/ktr.h> 37 #include <sys/lock.h> 38 #include <sys/proc.h> 39 #include <sys/mutex.h> 40 #include <sys/mbuf.h> 41 #include <sys/uio.h> 42 #include <sys/sysctl.h> 43 44 #include <vm/vm.h> 45 #include <vm/vm_page.h> 46 #include <vm/vm_map.h> 47 48 #include <machine/atomic.h> 49 #include <machine/bus.h> 50 #include <machine/md_var.h> 51 #include <machine/specialreg.h> 52 53 #define MAX_BPAGES 8192 54 55 struct bounce_zone; 56 57 struct bus_dma_tag { 58 bus_dma_tag_t parent; 59 bus_size_t alignment; 60 bus_size_t boundary; 61 bus_addr_t lowaddr; 62 bus_addr_t highaddr; 63 bus_dma_filter_t *filter; 64 void *filterarg; 65 bus_size_t maxsize; 66 u_int nsegments; 67 bus_size_t maxsegsz; 68 int flags; 69 int ref_count; 70 int map_count; 71 bus_dma_lock_t *lockfunc; 72 void *lockfuncarg; 73 bus_dma_segment_t *segments; 74 struct bounce_zone *bounce_zone; 75 }; 76 77 struct bounce_page { 78 vm_offset_t vaddr; /* kva of bounce buffer */ 79 bus_addr_t busaddr; /* Physical address */ 80 vm_offset_t datavaddr; /* kva of client data */ 81 bus_size_t datacount; /* client data count */ 82 STAILQ_ENTRY(bounce_page) links; 83 }; 84 85 int busdma_swi_pending; 86 87 struct bounce_zone { 88 STAILQ_ENTRY(bounce_zone) links; 89 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 90 int total_bpages; 91 int free_bpages; 92 int reserved_bpages; 93 int active_bpages; 94 int total_bounced; 95 int total_deferred; 96 int map_count; 97 bus_size_t alignment; 98 bus_addr_t lowaddr; 99 char zoneid[8]; 100 char lowaddrid[20]; 101 struct sysctl_ctx_list sysctl_tree; 102 struct sysctl_oid *sysctl_tree_top; 103 }; 104 105 static struct mtx bounce_lock; 106 static int total_bpages; 107 static int busdma_zonecount; 108 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 109 110 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 111 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 112 "Total bounce pages"); 113 114 struct bus_dmamap { 115 struct bp_list bpages; 116 int pagesneeded; 117 int pagesreserved; 118 bus_dma_tag_t dmat; 119 void *buf; /* unmapped buffer pointer */ 120 bus_size_t buflen; /* unmapped buffer length */ 121 bus_dmamap_callback_t *callback; 122 void *callback_arg; 123 STAILQ_ENTRY(bus_dmamap) links; 124 }; 125 126 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 128 static struct bus_dmamap nobounce_dmamap; 129 130 static void init_bounce_pages(void *dummy); 131 static int alloc_bounce_zone(bus_dma_tag_t dmat); 132 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 133 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 134 int commit); 135 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 136 vm_offset_t vaddr, bus_size_t size); 137 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 138 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 139 140 /* 141 * Return true if a match is made. 142 * 143 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 144 * 145 * If paddr is within the bounds of the dma tag then call the filter callback 146 * to check for a match, if there is no filter callback then assume a match. 147 */ 148 static __inline int 149 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 150 { 151 int retval; 152 153 retval = 0; 154 155 do { 156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 157 || ((paddr & (dmat->alignment - 1)) != 0)) 158 && (dmat->filter == NULL 159 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 160 retval = 1; 161 162 dmat = dmat->parent; 163 } while (retval == 0 && dmat != NULL); 164 return (retval); 165 } 166 167 /* 168 * Convenience function for manipulating driver locks from busdma (during 169 * busdma_swi, for example). Drivers that don't provide their own locks 170 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 171 * non-mutex locking scheme don't have to use this at all. 172 */ 173 void 174 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 175 { 176 struct mtx *dmtx; 177 178 dmtx = (struct mtx *)arg; 179 switch (op) { 180 case BUS_DMA_LOCK: 181 mtx_lock(dmtx); 182 break; 183 case BUS_DMA_UNLOCK: 184 mtx_unlock(dmtx); 185 break; 186 default: 187 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 188 } 189 } 190 191 /* 192 * dflt_lock should never get called. It gets put into the dma tag when 193 * lockfunc == NULL, which is only valid if the maps that are associated 194 * with the tag are meant to never be defered. 195 * XXX Should have a way to identify which driver is responsible here. 196 */ 197 static void 198 dflt_lock(void *arg, bus_dma_lock_op_t op) 199 { 200 panic("driver error: busdma dflt_lock called"); 201 } 202 203 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 204 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 205 /* 206 * Allocate a device specific dma_tag. 207 */ 208 int 209 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 210 bus_size_t boundary, bus_addr_t lowaddr, 211 bus_addr_t highaddr, bus_dma_filter_t *filter, 212 void *filterarg, bus_size_t maxsize, int nsegments, 213 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 214 void *lockfuncarg, bus_dma_tag_t *dmat) 215 { 216 bus_dma_tag_t newtag; 217 int error = 0; 218 219 /* Always enforce at least a 4GB boundary. */ 220 if (boundary == 0 || boundary > ((bus_addr_t)1 << 32)) 221 boundary = (bus_size_t)1 << 32; 222 223 /* Basic sanity checking */ 224 if (boundary != 0 && boundary < maxsegsz) 225 maxsegsz = boundary; 226 227 if (maxsegsz == 0) { 228 return (EINVAL); 229 } 230 231 /* Return a NULL tag on failure */ 232 *dmat = NULL; 233 234 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 235 M_ZERO | M_NOWAIT); 236 if (newtag == NULL) { 237 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 238 __func__, newtag, 0, error); 239 return (ENOMEM); 240 } 241 242 newtag->parent = parent; 243 newtag->alignment = alignment; 244 newtag->boundary = boundary; 245 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 246 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 247 newtag->filter = filter; 248 newtag->filterarg = filterarg; 249 newtag->maxsize = maxsize; 250 newtag->nsegments = nsegments; 251 newtag->maxsegsz = maxsegsz; 252 newtag->flags = flags; 253 newtag->ref_count = 1; /* Count ourself */ 254 newtag->map_count = 0; 255 if (lockfunc != NULL) { 256 newtag->lockfunc = lockfunc; 257 newtag->lockfuncarg = lockfuncarg; 258 } else { 259 newtag->lockfunc = dflt_lock; 260 newtag->lockfuncarg = NULL; 261 } 262 newtag->segments = NULL; 263 264 /* Take into account any restrictions imposed by our parent tag */ 265 if (parent != NULL) { 266 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 267 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 268 if (newtag->boundary == 0) 269 newtag->boundary = parent->boundary; 270 else if (parent->boundary != 0) 271 newtag->boundary = MIN(parent->boundary, 272 newtag->boundary); 273 if (newtag->filter == NULL) { 274 /* 275 * Short circuit looking at our parent directly 276 * since we have encapsulated all of its information 277 */ 278 newtag->filter = parent->filter; 279 newtag->filterarg = parent->filterarg; 280 newtag->parent = parent->parent; 281 } 282 if (newtag->parent != NULL) 283 atomic_add_int(&parent->ref_count, 1); 284 } 285 286 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 287 || newtag->alignment > 1) 288 newtag->flags |= BUS_DMA_COULD_BOUNCE; 289 290 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 291 (flags & BUS_DMA_ALLOCNOW) != 0) { 292 struct bounce_zone *bz; 293 294 /* Must bounce */ 295 296 if ((error = alloc_bounce_zone(newtag)) != 0) { 297 free(newtag, M_DEVBUF); 298 return (error); 299 } 300 bz = newtag->bounce_zone; 301 302 if (ptoa(bz->total_bpages) < maxsize) { 303 int pages; 304 305 pages = atop(maxsize) - bz->total_bpages; 306 307 /* Add pages to our bounce pool */ 308 if (alloc_bounce_pages(newtag, pages) < pages) 309 error = ENOMEM; 310 } 311 /* Performed initial allocation */ 312 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 313 } 314 315 if (error != 0) { 316 free(newtag, M_DEVBUF); 317 } else { 318 *dmat = newtag; 319 } 320 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 321 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 322 return (error); 323 } 324 325 int 326 bus_dma_tag_destroy(bus_dma_tag_t dmat) 327 { 328 bus_dma_tag_t dmat_copy; 329 int error; 330 331 error = 0; 332 dmat_copy = dmat; 333 334 if (dmat != NULL) { 335 336 if (dmat->map_count != 0) { 337 error = EBUSY; 338 goto out; 339 } 340 341 while (dmat != NULL) { 342 bus_dma_tag_t parent; 343 344 parent = dmat->parent; 345 atomic_subtract_int(&dmat->ref_count, 1); 346 if (dmat->ref_count == 0) { 347 if (dmat->segments != NULL) 348 free(dmat->segments, M_DEVBUF); 349 free(dmat, M_DEVBUF); 350 /* 351 * Last reference count, so 352 * release our reference 353 * count on our parent. 354 */ 355 dmat = parent; 356 } else 357 dmat = NULL; 358 } 359 } 360 out: 361 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 362 return (error); 363 } 364 365 /* 366 * Allocate a handle for mapping from kva/uva/physical 367 * address space into bus device space. 368 */ 369 int 370 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 371 { 372 int error; 373 374 error = 0; 375 376 if (dmat->segments == NULL) { 377 dmat->segments = (bus_dma_segment_t *)malloc( 378 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 379 M_NOWAIT); 380 if (dmat->segments == NULL) { 381 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 382 __func__, dmat, ENOMEM); 383 return (ENOMEM); 384 } 385 } 386 387 /* 388 * Bouncing might be required if the driver asks for an active 389 * exclusion region, a data alignment that is stricter than 1, and/or 390 * an active address boundary. 391 */ 392 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 393 394 /* Must bounce */ 395 struct bounce_zone *bz; 396 int maxpages; 397 398 if (dmat->bounce_zone == NULL) { 399 if ((error = alloc_bounce_zone(dmat)) != 0) 400 return (error); 401 } 402 bz = dmat->bounce_zone; 403 404 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 405 M_NOWAIT | M_ZERO); 406 if (*mapp == NULL) { 407 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 408 __func__, dmat, ENOMEM); 409 return (ENOMEM); 410 } 411 412 /* Initialize the new map */ 413 STAILQ_INIT(&((*mapp)->bpages)); 414 415 /* 416 * Attempt to add pages to our pool on a per-instance 417 * basis up to a sane limit. 418 */ 419 if (dmat->alignment > 1) 420 maxpages = MAX_BPAGES; 421 else 422 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 423 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 424 || (bz->map_count > 0 && bz->total_bpages < maxpages)) { 425 int pages; 426 427 pages = MAX(atop(dmat->maxsize), 1); 428 pages = MIN(maxpages - bz->total_bpages, pages); 429 pages = MAX(pages, 1); 430 if (alloc_bounce_pages(dmat, pages) < pages) 431 error = ENOMEM; 432 433 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 434 if (error == 0) 435 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 436 } else { 437 error = 0; 438 } 439 } 440 bz->map_count++; 441 } else { 442 *mapp = NULL; 443 } 444 if (error == 0) 445 dmat->map_count++; 446 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 447 __func__, dmat, dmat->flags, error); 448 return (error); 449 } 450 451 /* 452 * Destroy a handle for mapping from kva/uva/physical 453 * address space into bus device space. 454 */ 455 int 456 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 457 { 458 if (map != NULL && map != &nobounce_dmamap) { 459 if (STAILQ_FIRST(&map->bpages) != NULL) { 460 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 461 __func__, dmat, EBUSY); 462 return (EBUSY); 463 } 464 if (dmat->bounce_zone) 465 dmat->bounce_zone->map_count--; 466 free(map, M_DEVBUF); 467 } 468 dmat->map_count--; 469 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 470 return (0); 471 } 472 473 474 /* 475 * Allocate a piece of memory that can be efficiently mapped into 476 * bus device space based on the constraints lited in the dma tag. 477 * A dmamap to for use with dmamap_load is also allocated. 478 */ 479 int 480 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 481 bus_dmamap_t *mapp) 482 { 483 int mflags; 484 485 if (flags & BUS_DMA_NOWAIT) 486 mflags = M_NOWAIT; 487 else 488 mflags = M_WAITOK; 489 490 /* If we succeed, no mapping/bouncing will be required */ 491 *mapp = NULL; 492 493 if (dmat->segments == NULL) { 494 dmat->segments = (bus_dma_segment_t *)malloc( 495 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 496 mflags); 497 if (dmat->segments == NULL) { 498 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 499 __func__, dmat, dmat->flags, ENOMEM); 500 return (ENOMEM); 501 } 502 } 503 if (flags & BUS_DMA_ZERO) 504 mflags |= M_ZERO; 505 506 /* 507 * XXX: 508 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 509 * alignment guarantees of malloc need to be nailed down, and the 510 * code below should be rewritten to take that into account. 511 * 512 * In the meantime, we'll warn the user if malloc gets it wrong. 513 */ 514 if ((dmat->maxsize <= PAGE_SIZE) && 515 (dmat->alignment < dmat->maxsize) && 516 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 517 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 518 } else { 519 /* 520 * XXX Use Contigmalloc until it is merged into this facility 521 * and handles multi-seg allocations. Nobody is doing 522 * multi-seg allocations yet though. 523 * XXX Certain AGP hardware does. 524 */ 525 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 526 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 527 dmat->boundary); 528 } 529 if (*vaddr == NULL) { 530 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 531 __func__, dmat, dmat->flags, ENOMEM); 532 return (ENOMEM); 533 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 534 printf("bus_dmamem_alloc failed to align memory properly.\n"); 535 } 536 if (flags & BUS_DMA_NOCACHE) 537 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 538 PAT_UNCACHEABLE); 539 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 540 __func__, dmat, dmat->flags, 0); 541 return (0); 542 } 543 544 /* 545 * Free a piece of memory and it's allociated dmamap, that was allocated 546 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 547 */ 548 void 549 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 550 { 551 /* 552 * dmamem does not need to be bounced, so the map should be 553 * NULL 554 */ 555 if (map != NULL) 556 panic("bus_dmamem_free: Invalid map freed\n"); 557 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 558 if ((dmat->maxsize <= PAGE_SIZE) && 559 (dmat->alignment < dmat->maxsize) && 560 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 561 free(vaddr, M_DEVBUF); 562 else { 563 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 564 } 565 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 566 } 567 568 /* 569 * Utility function to load a linear buffer. lastaddrp holds state 570 * between invocations (for multiple-buffer loads). segp contains 571 * the starting segment on entrace, and the ending segment on exit. 572 * first indicates if this is the first invocation of this function. 573 */ 574 static __inline int 575 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 576 bus_dmamap_t map, 577 void *buf, bus_size_t buflen, 578 pmap_t pmap, 579 int flags, 580 bus_addr_t *lastaddrp, 581 bus_dma_segment_t *segs, 582 int *segp, 583 int first) 584 { 585 bus_size_t sgsize; 586 bus_addr_t curaddr, lastaddr, baddr, bmask; 587 vm_offset_t vaddr; 588 bus_addr_t paddr; 589 int seg; 590 591 if (map == NULL) 592 map = &nobounce_dmamap; 593 594 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 595 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 596 vm_offset_t vendaddr; 597 598 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 599 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 600 dmat->boundary, dmat->alignment); 601 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 602 map, &nobounce_dmamap, map->pagesneeded); 603 /* 604 * Count the number of bounce pages 605 * needed in order to complete this transfer 606 */ 607 vaddr = (vm_offset_t)buf; 608 vendaddr = (vm_offset_t)buf + buflen; 609 610 while (vaddr < vendaddr) { 611 bus_size_t sg_len; 612 613 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 614 if (pmap) 615 paddr = pmap_extract(pmap, vaddr); 616 else 617 paddr = pmap_kextract(vaddr); 618 if (run_filter(dmat, paddr) != 0) { 619 sg_len = roundup2(sg_len, dmat->alignment); 620 map->pagesneeded++; 621 } 622 vaddr += sg_len; 623 } 624 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 625 } 626 627 /* Reserve Necessary Bounce Pages */ 628 if (map->pagesneeded != 0) { 629 mtx_lock(&bounce_lock); 630 if (flags & BUS_DMA_NOWAIT) { 631 if (reserve_bounce_pages(dmat, map, 0) != 0) { 632 mtx_unlock(&bounce_lock); 633 return (ENOMEM); 634 } 635 } else { 636 if (reserve_bounce_pages(dmat, map, 1) != 0) { 637 /* Queue us for resources */ 638 map->dmat = dmat; 639 map->buf = buf; 640 map->buflen = buflen; 641 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 642 map, links); 643 mtx_unlock(&bounce_lock); 644 return (EINPROGRESS); 645 } 646 } 647 mtx_unlock(&bounce_lock); 648 } 649 650 vaddr = (vm_offset_t)buf; 651 lastaddr = *lastaddrp; 652 bmask = ~(dmat->boundary - 1); 653 654 for (seg = *segp; buflen > 0 ; ) { 655 bus_size_t max_sgsize; 656 657 /* 658 * Get the physical address for this segment. 659 */ 660 if (pmap) 661 curaddr = pmap_extract(pmap, vaddr); 662 else 663 curaddr = pmap_kextract(vaddr); 664 665 /* 666 * Compute the segment size, and adjust counts. 667 */ 668 max_sgsize = MIN(buflen, dmat->maxsegsz); 669 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); 670 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 671 sgsize = roundup2(sgsize, dmat->alignment); 672 sgsize = MIN(sgsize, max_sgsize); 673 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 674 } else { 675 sgsize = MIN(sgsize, max_sgsize); 676 } 677 678 /* 679 * Make sure we don't cross any boundaries. 680 */ 681 if (dmat->boundary > 0) { 682 baddr = (curaddr + dmat->boundary) & bmask; 683 if (sgsize > (baddr - curaddr)) 684 sgsize = (baddr - curaddr); 685 } 686 687 /* 688 * Insert chunk into a segment, coalescing with 689 * previous segment if possible. 690 */ 691 if (first) { 692 segs[seg].ds_addr = curaddr; 693 segs[seg].ds_len = sgsize; 694 first = 0; 695 } else { 696 if (curaddr == lastaddr && 697 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 698 (dmat->boundary == 0 || 699 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 700 segs[seg].ds_len += sgsize; 701 else { 702 if (++seg >= dmat->nsegments) 703 break; 704 segs[seg].ds_addr = curaddr; 705 segs[seg].ds_len = sgsize; 706 } 707 } 708 709 lastaddr = curaddr + sgsize; 710 vaddr += sgsize; 711 buflen -= sgsize; 712 } 713 714 *segp = seg; 715 *lastaddrp = lastaddr; 716 717 /* 718 * Did we fit? 719 */ 720 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 721 } 722 723 /* 724 * Map the buffer buf into bus space using the dmamap map. 725 */ 726 int 727 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 728 bus_size_t buflen, bus_dmamap_callback_t *callback, 729 void *callback_arg, int flags) 730 { 731 bus_addr_t lastaddr = 0; 732 int error, nsegs = 0; 733 734 if (map != NULL) { 735 flags |= BUS_DMA_WAITOK; 736 map->callback = callback; 737 map->callback_arg = callback_arg; 738 } 739 740 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 741 &lastaddr, dmat->segments, &nsegs, 1); 742 743 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 744 __func__, dmat, dmat->flags, error, nsegs + 1); 745 746 if (error == EINPROGRESS) { 747 return (error); 748 } 749 750 if (error) 751 (*callback)(callback_arg, dmat->segments, 0, error); 752 else 753 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 754 755 /* 756 * Return ENOMEM to the caller so that it can pass it up the stack. 757 * This error only happens when NOWAIT is set, so deferal is disabled. 758 */ 759 if (error == ENOMEM) 760 return (error); 761 762 return (0); 763 } 764 765 766 /* 767 * Like _bus_dmamap_load(), but for mbufs. 768 */ 769 int 770 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 771 struct mbuf *m0, 772 bus_dmamap_callback2_t *callback, void *callback_arg, 773 int flags) 774 { 775 int nsegs, error; 776 777 M_ASSERTPKTHDR(m0); 778 779 flags |= BUS_DMA_NOWAIT; 780 nsegs = 0; 781 error = 0; 782 if (m0->m_pkthdr.len <= dmat->maxsize) { 783 int first = 1; 784 bus_addr_t lastaddr = 0; 785 struct mbuf *m; 786 787 for (m = m0; m != NULL && error == 0; m = m->m_next) { 788 if (m->m_len > 0) { 789 error = _bus_dmamap_load_buffer(dmat, map, 790 m->m_data, m->m_len, 791 NULL, flags, &lastaddr, 792 dmat->segments, &nsegs, first); 793 first = 0; 794 } 795 } 796 } else { 797 error = EINVAL; 798 } 799 800 if (error) { 801 /* force "no valid mappings" in callback */ 802 (*callback)(callback_arg, dmat->segments, 0, 0, error); 803 } else { 804 (*callback)(callback_arg, dmat->segments, 805 nsegs+1, m0->m_pkthdr.len, error); 806 } 807 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 808 __func__, dmat, dmat->flags, error, nsegs + 1); 809 return (error); 810 } 811 812 int 813 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 814 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 815 int flags) 816 { 817 int error; 818 819 M_ASSERTPKTHDR(m0); 820 821 flags |= BUS_DMA_NOWAIT; 822 *nsegs = 0; 823 error = 0; 824 if (m0->m_pkthdr.len <= dmat->maxsize) { 825 int first = 1; 826 bus_addr_t lastaddr = 0; 827 struct mbuf *m; 828 829 for (m = m0; m != NULL && error == 0; m = m->m_next) { 830 if (m->m_len > 0) { 831 error = _bus_dmamap_load_buffer(dmat, map, 832 m->m_data, m->m_len, 833 NULL, flags, &lastaddr, 834 segs, nsegs, first); 835 first = 0; 836 } 837 } 838 } else { 839 error = EINVAL; 840 } 841 842 /* XXX FIXME: Having to increment nsegs is really annoying */ 843 ++*nsegs; 844 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 845 __func__, dmat, dmat->flags, error, *nsegs); 846 return (error); 847 } 848 849 /* 850 * Like _bus_dmamap_load(), but for uios. 851 */ 852 int 853 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 854 struct uio *uio, 855 bus_dmamap_callback2_t *callback, void *callback_arg, 856 int flags) 857 { 858 bus_addr_t lastaddr = 0; 859 int nsegs, error, first, i; 860 bus_size_t resid; 861 struct iovec *iov; 862 pmap_t pmap; 863 864 flags |= BUS_DMA_NOWAIT; 865 resid = uio->uio_resid; 866 iov = uio->uio_iov; 867 868 if (uio->uio_segflg == UIO_USERSPACE) { 869 KASSERT(uio->uio_td != NULL, 870 ("bus_dmamap_load_uio: USERSPACE but no proc")); 871 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 872 } else 873 pmap = NULL; 874 875 nsegs = 0; 876 error = 0; 877 first = 1; 878 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 879 /* 880 * Now at the first iovec to load. Load each iovec 881 * until we have exhausted the residual count. 882 */ 883 bus_size_t minlen = 884 resid < iov[i].iov_len ? resid : iov[i].iov_len; 885 caddr_t addr = (caddr_t) iov[i].iov_base; 886 887 if (minlen > 0) { 888 error = _bus_dmamap_load_buffer(dmat, map, 889 addr, minlen, pmap, flags, &lastaddr, 890 dmat->segments, &nsegs, first); 891 first = 0; 892 893 resid -= minlen; 894 } 895 } 896 897 if (error) { 898 /* force "no valid mappings" in callback */ 899 (*callback)(callback_arg, dmat->segments, 0, 0, error); 900 } else { 901 (*callback)(callback_arg, dmat->segments, 902 nsegs+1, uio->uio_resid, error); 903 } 904 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 905 __func__, dmat, dmat->flags, error, nsegs + 1); 906 return (error); 907 } 908 909 /* 910 * Release the mapping held by map. 911 */ 912 void 913 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 914 { 915 struct bounce_page *bpage; 916 917 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 918 STAILQ_REMOVE_HEAD(&map->bpages, links); 919 free_bounce_page(dmat, bpage); 920 } 921 } 922 923 void 924 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 925 { 926 struct bounce_page *bpage; 927 928 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 929 /* 930 * Handle data bouncing. We might also 931 * want to add support for invalidating 932 * the caches on broken hardware 933 */ 934 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 935 "performing bounce", __func__, op, dmat, dmat->flags); 936 937 if (op & BUS_DMASYNC_PREWRITE) { 938 while (bpage != NULL) { 939 bcopy((void *)bpage->datavaddr, 940 (void *)bpage->vaddr, 941 bpage->datacount); 942 bpage = STAILQ_NEXT(bpage, links); 943 } 944 dmat->bounce_zone->total_bounced++; 945 } 946 947 if (op & BUS_DMASYNC_POSTREAD) { 948 while (bpage != NULL) { 949 bcopy((void *)bpage->vaddr, 950 (void *)bpage->datavaddr, 951 bpage->datacount); 952 bpage = STAILQ_NEXT(bpage, links); 953 } 954 dmat->bounce_zone->total_bounced++; 955 } 956 } 957 } 958 959 static void 960 init_bounce_pages(void *dummy __unused) 961 { 962 963 total_bpages = 0; 964 STAILQ_INIT(&bounce_zone_list); 965 STAILQ_INIT(&bounce_map_waitinglist); 966 STAILQ_INIT(&bounce_map_callbacklist); 967 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 968 } 969 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 970 971 static struct sysctl_ctx_list * 972 busdma_sysctl_tree(struct bounce_zone *bz) 973 { 974 return (&bz->sysctl_tree); 975 } 976 977 static struct sysctl_oid * 978 busdma_sysctl_tree_top(struct bounce_zone *bz) 979 { 980 return (bz->sysctl_tree_top); 981 } 982 983 static int 984 alloc_bounce_zone(bus_dma_tag_t dmat) 985 { 986 struct bounce_zone *bz; 987 988 /* Check to see if we already have a suitable zone */ 989 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 990 if ((dmat->alignment <= bz->alignment) 991 && (dmat->lowaddr >= bz->lowaddr)) { 992 dmat->bounce_zone = bz; 993 return (0); 994 } 995 } 996 997 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 998 M_NOWAIT | M_ZERO)) == NULL) 999 return (ENOMEM); 1000 1001 STAILQ_INIT(&bz->bounce_page_list); 1002 bz->free_bpages = 0; 1003 bz->reserved_bpages = 0; 1004 bz->active_bpages = 0; 1005 bz->lowaddr = dmat->lowaddr; 1006 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 1007 bz->map_count = 0; 1008 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1009 busdma_zonecount++; 1010 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1011 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1012 dmat->bounce_zone = bz; 1013 1014 sysctl_ctx_init(&bz->sysctl_tree); 1015 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1016 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1017 CTLFLAG_RD, 0, ""); 1018 if (bz->sysctl_tree_top == NULL) { 1019 sysctl_ctx_free(&bz->sysctl_tree); 1020 return (0); /* XXX error code? */ 1021 } 1022 1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1025 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1026 "Total bounce pages"); 1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1029 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1030 "Free bounce pages"); 1031 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1032 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1033 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1034 "Reserved bounce pages"); 1035 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1036 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1037 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1038 "Active bounce pages"); 1039 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1040 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1041 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1042 "Total bounce requests"); 1043 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1045 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1046 "Total bounce requests that were deferred"); 1047 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1048 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1049 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1050 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1052 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1053 1054 return (0); 1055 } 1056 1057 static int 1058 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1059 { 1060 struct bounce_zone *bz; 1061 int count; 1062 1063 bz = dmat->bounce_zone; 1064 count = 0; 1065 while (numpages > 0) { 1066 struct bounce_page *bpage; 1067 1068 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1069 M_NOWAIT | M_ZERO); 1070 1071 if (bpage == NULL) 1072 break; 1073 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1074 M_NOWAIT, 0ul, 1075 bz->lowaddr, 1076 PAGE_SIZE, 1077 0); 1078 if (bpage->vaddr == 0) { 1079 free(bpage, M_DEVBUF); 1080 break; 1081 } 1082 bpage->busaddr = pmap_kextract(bpage->vaddr); 1083 mtx_lock(&bounce_lock); 1084 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1085 total_bpages++; 1086 bz->total_bpages++; 1087 bz->free_bpages++; 1088 mtx_unlock(&bounce_lock); 1089 count++; 1090 numpages--; 1091 } 1092 return (count); 1093 } 1094 1095 static int 1096 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1097 { 1098 struct bounce_zone *bz; 1099 int pages; 1100 1101 mtx_assert(&bounce_lock, MA_OWNED); 1102 bz = dmat->bounce_zone; 1103 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1104 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1105 return (map->pagesneeded - (map->pagesreserved + pages)); 1106 bz->free_bpages -= pages; 1107 bz->reserved_bpages += pages; 1108 map->pagesreserved += pages; 1109 pages = map->pagesneeded - map->pagesreserved; 1110 1111 return (pages); 1112 } 1113 1114 static bus_addr_t 1115 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1116 bus_size_t size) 1117 { 1118 struct bounce_zone *bz; 1119 struct bounce_page *bpage; 1120 1121 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1122 KASSERT(map != NULL && map != &nobounce_dmamap, 1123 ("add_bounce_page: bad map %p", map)); 1124 1125 bz = dmat->bounce_zone; 1126 if (map->pagesneeded == 0) 1127 panic("add_bounce_page: map doesn't need any pages"); 1128 map->pagesneeded--; 1129 1130 if (map->pagesreserved == 0) 1131 panic("add_bounce_page: map doesn't need any pages"); 1132 map->pagesreserved--; 1133 1134 mtx_lock(&bounce_lock); 1135 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1136 if (bpage == NULL) 1137 panic("add_bounce_page: free page list is empty"); 1138 1139 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1140 bz->reserved_bpages--; 1141 bz->active_bpages++; 1142 mtx_unlock(&bounce_lock); 1143 1144 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1145 /* Page offset needs to be preserved. */ 1146 bpage->vaddr |= vaddr & PAGE_MASK; 1147 bpage->busaddr |= vaddr & PAGE_MASK; 1148 } 1149 bpage->datavaddr = vaddr; 1150 bpage->datacount = size; 1151 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1152 return (bpage->busaddr); 1153 } 1154 1155 static void 1156 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1157 { 1158 struct bus_dmamap *map; 1159 struct bounce_zone *bz; 1160 1161 bz = dmat->bounce_zone; 1162 bpage->datavaddr = 0; 1163 bpage->datacount = 0; 1164 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1165 /* 1166 * Reset the bounce page to start at offset 0. Other uses 1167 * of this bounce page may need to store a full page of 1168 * data and/or assume it starts on a page boundary. 1169 */ 1170 bpage->vaddr &= ~PAGE_MASK; 1171 bpage->busaddr &= ~PAGE_MASK; 1172 } 1173 1174 mtx_lock(&bounce_lock); 1175 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1176 bz->free_bpages++; 1177 bz->active_bpages--; 1178 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1179 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1180 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1181 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1182 map, links); 1183 busdma_swi_pending = 1; 1184 bz->total_deferred++; 1185 swi_sched(vm_ih, 0); 1186 } 1187 } 1188 mtx_unlock(&bounce_lock); 1189 } 1190 1191 void 1192 busdma_swi(void) 1193 { 1194 bus_dma_tag_t dmat; 1195 struct bus_dmamap *map; 1196 1197 mtx_lock(&bounce_lock); 1198 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1199 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1200 mtx_unlock(&bounce_lock); 1201 dmat = map->dmat; 1202 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1203 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1204 map->callback, map->callback_arg, /*flags*/0); 1205 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1206 mtx_lock(&bounce_lock); 1207 } 1208 mtx_unlock(&bounce_lock); 1209 }
Cache object: 0dab658facdcf703d102288c697834e1
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