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sys/i386/i386/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/8.2/sys/i386/i386/busdma_machdep.c 216305 2010-12-08 19:48:29Z cperciva $"); 29 30 #include <sys/param.h> 31 #include <sys/kdb.h> 32 #include <ddb/ddb.h> 33 #include <ddb/db_output.h> 34 #include <sys/systm.h> 35 #include <sys/malloc.h> 36 #include <sys/bus.h> 37 #include <sys/interrupt.h> 38 #include <sys/kernel.h> 39 #include <sys/ktr.h> 40 #include <sys/lock.h> 41 #include <sys/proc.h> 42 #include <sys/mutex.h> 43 #include <sys/mbuf.h> 44 #include <sys/uio.h> 45 #include <sys/sysctl.h> 46 47 #include <vm/vm.h> 48 #include <vm/vm_page.h> 49 #include <vm/vm_map.h> 50 51 #include <machine/atomic.h> 52 #include <machine/bus.h> 53 #include <machine/md_var.h> 54 #include <machine/specialreg.h> 55 56 #define MAX_BPAGES 512 57 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 58 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 59 60 struct bounce_zone; 61 62 struct bus_dma_tag { 63 bus_dma_tag_t parent; 64 bus_size_t alignment; 65 bus_size_t boundary; 66 bus_addr_t lowaddr; 67 bus_addr_t highaddr; 68 bus_dma_filter_t *filter; 69 void *filterarg; 70 bus_size_t maxsize; 71 u_int nsegments; 72 bus_size_t maxsegsz; 73 int flags; 74 int ref_count; 75 int map_count; 76 bus_dma_lock_t *lockfunc; 77 void *lockfuncarg; 78 bus_dma_segment_t *segments; 79 struct bounce_zone *bounce_zone; 80 }; 81 82 struct bounce_page { 83 vm_offset_t vaddr; /* kva of bounce buffer */ 84 bus_addr_t busaddr; /* Physical address */ 85 vm_offset_t datavaddr; /* kva of client data */ 86 bus_size_t datacount; /* client data count */ 87 STAILQ_ENTRY(bounce_page) links; 88 }; 89 90 int busdma_swi_pending; 91 92 struct bounce_zone { 93 STAILQ_ENTRY(bounce_zone) links; 94 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 95 int total_bpages; 96 int free_bpages; 97 int reserved_bpages; 98 int active_bpages; 99 int total_bounced; 100 int total_deferred; 101 int map_count; 102 bus_size_t alignment; 103 bus_addr_t lowaddr; 104 char zoneid[8]; 105 char lowaddrid[20]; 106 struct sysctl_ctx_list sysctl_tree; 107 struct sysctl_oid *sysctl_tree_top; 108 }; 109 110 static struct mtx bounce_lock; 111 static int total_bpages; 112 static int busdma_zonecount; 113 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 114 115 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 116 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 117 "Total bounce pages"); 118 119 struct bus_dmamap { 120 struct bp_list bpages; 121 int pagesneeded; 122 int pagesreserved; 123 bus_dma_tag_t dmat; 124 void *buf; /* unmapped buffer pointer */ 125 bus_size_t buflen; /* unmapped buffer length */ 126 bus_dmamap_callback_t *callback; 127 void *callback_arg; 128 STAILQ_ENTRY(bus_dmamap) links; 129 }; 130 131 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 132 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 133 static struct bus_dmamap nobounce_dmamap; 134 135 static void init_bounce_pages(void *dummy); 136 static int alloc_bounce_zone(bus_dma_tag_t dmat); 137 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 138 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 139 int commit); 140 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 141 vm_offset_t vaddr, bus_size_t size); 142 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 143 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 144 int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 145 void *buf, bus_size_t buflen, int flags); 146 147 #ifdef XEN 148 #undef pmap_kextract 149 #define pmap_kextract pmap_kextract_ma 150 #endif 151 152 /* 153 * Return true if a match is made. 154 * 155 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 156 * 157 * If paddr is within the bounds of the dma tag then call the filter callback 158 * to check for a match, if there is no filter callback then assume a match. 159 */ 160 int 161 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 162 { 163 int retval; 164 165 retval = 0; 166 167 do { 168 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 169 || ((paddr & (dmat->alignment - 1)) != 0)) 170 && (dmat->filter == NULL 171 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 172 retval = 1; 173 174 dmat = dmat->parent; 175 } while (retval == 0 && dmat != NULL); 176 return (retval); 177 } 178 179 /* 180 * Convenience function for manipulating driver locks from busdma (during 181 * busdma_swi, for example). Drivers that don't provide their own locks 182 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 183 * non-mutex locking scheme don't have to use this at all. 184 */ 185 void 186 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 187 { 188 struct mtx *dmtx; 189 190 dmtx = (struct mtx *)arg; 191 switch (op) { 192 case BUS_DMA_LOCK: 193 mtx_lock(dmtx); 194 break; 195 case BUS_DMA_UNLOCK: 196 mtx_unlock(dmtx); 197 break; 198 default: 199 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 200 } 201 } 202 203 /* 204 * dflt_lock should never get called. It gets put into the dma tag when 205 * lockfunc == NULL, which is only valid if the maps that are associated 206 * with the tag are meant to never be defered. 207 * XXX Should have a way to identify which driver is responsible here. 208 */ 209 static void 210 dflt_lock(void *arg, bus_dma_lock_op_t op) 211 { 212 panic("driver error: busdma dflt_lock called"); 213 } 214 215 /* 216 * Allocate a device specific dma_tag. 217 */ 218 int 219 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 220 bus_size_t boundary, bus_addr_t lowaddr, 221 bus_addr_t highaddr, bus_dma_filter_t *filter, 222 void *filterarg, bus_size_t maxsize, int nsegments, 223 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 224 void *lockfuncarg, bus_dma_tag_t *dmat) 225 { 226 bus_dma_tag_t newtag; 227 int error = 0; 228 229 /* Basic sanity checking */ 230 if (boundary != 0 && boundary < maxsegsz) 231 maxsegsz = boundary; 232 233 if (maxsegsz == 0) { 234 return (EINVAL); 235 } 236 237 /* Return a NULL tag on failure */ 238 *dmat = NULL; 239 240 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 241 M_ZERO | M_NOWAIT); 242 if (newtag == NULL) { 243 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 244 __func__, newtag, 0, error); 245 return (ENOMEM); 246 } 247 248 newtag->parent = parent; 249 newtag->alignment = alignment; 250 newtag->boundary = boundary; 251 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 252 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1); 253 newtag->filter = filter; 254 newtag->filterarg = filterarg; 255 newtag->maxsize = maxsize; 256 newtag->nsegments = nsegments; 257 newtag->maxsegsz = maxsegsz; 258 newtag->flags = flags; 259 newtag->ref_count = 1; /* Count ourself */ 260 newtag->map_count = 0; 261 if (lockfunc != NULL) { 262 newtag->lockfunc = lockfunc; 263 newtag->lockfuncarg = lockfuncarg; 264 } else { 265 newtag->lockfunc = dflt_lock; 266 newtag->lockfuncarg = NULL; 267 } 268 newtag->segments = NULL; 269 270 /* Take into account any restrictions imposed by our parent tag */ 271 if (parent != NULL) { 272 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 273 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 274 if (newtag->boundary == 0) 275 newtag->boundary = parent->boundary; 276 else if (parent->boundary != 0) 277 newtag->boundary = MIN(parent->boundary, 278 newtag->boundary); 279 if ((newtag->filter != NULL) || 280 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0)) 281 newtag->flags |= BUS_DMA_COULD_BOUNCE; 282 if (newtag->filter == NULL) { 283 /* 284 * Short circuit looking at our parent directly 285 * since we have encapsulated all of its information 286 */ 287 newtag->filter = parent->filter; 288 newtag->filterarg = parent->filterarg; 289 newtag->parent = parent->parent; 290 } 291 if (newtag->parent != NULL) 292 atomic_add_int(&parent->ref_count, 1); 293 } 294 295 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 296 || newtag->alignment > 1) 297 newtag->flags |= BUS_DMA_COULD_BOUNCE; 298 299 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 300 (flags & BUS_DMA_ALLOCNOW) != 0) { 301 struct bounce_zone *bz; 302 303 /* Must bounce */ 304 305 if ((error = alloc_bounce_zone(newtag)) != 0) { 306 free(newtag, M_DEVBUF); 307 return (error); 308 } 309 bz = newtag->bounce_zone; 310 311 if (ptoa(bz->total_bpages) < maxsize) { 312 int pages; 313 314 pages = atop(maxsize) - bz->total_bpages; 315 316 /* Add pages to our bounce pool */ 317 if (alloc_bounce_pages(newtag, pages) < pages) 318 error = ENOMEM; 319 } 320 /* Performed initial allocation */ 321 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 322 } 323 324 if (error != 0) { 325 free(newtag, M_DEVBUF); 326 } else { 327 *dmat = newtag; 328 } 329 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 330 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 331 return (error); 332 } 333 334 int 335 bus_dma_tag_destroy(bus_dma_tag_t dmat) 336 { 337 bus_dma_tag_t dmat_copy; 338 int error; 339 340 error = 0; 341 dmat_copy = dmat; 342 343 if (dmat != NULL) { 344 345 if (dmat->map_count != 0) { 346 error = EBUSY; 347 goto out; 348 } 349 350 while (dmat != NULL) { 351 bus_dma_tag_t parent; 352 353 parent = dmat->parent; 354 atomic_subtract_int(&dmat->ref_count, 1); 355 if (dmat->ref_count == 0) { 356 if (dmat->segments != NULL) 357 free(dmat->segments, M_DEVBUF); 358 free(dmat, M_DEVBUF); 359 /* 360 * Last reference count, so 361 * release our reference 362 * count on our parent. 363 */ 364 dmat = parent; 365 } else 366 dmat = NULL; 367 } 368 } 369 out: 370 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 371 return (error); 372 } 373 374 /* 375 * Allocate a handle for mapping from kva/uva/physical 376 * address space into bus device space. 377 */ 378 int 379 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 380 { 381 int error; 382 383 error = 0; 384 385 if (dmat->segments == NULL) { 386 dmat->segments = (bus_dma_segment_t *)malloc( 387 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 388 M_NOWAIT); 389 if (dmat->segments == NULL) { 390 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 391 __func__, dmat, ENOMEM); 392 return (ENOMEM); 393 } 394 } 395 396 /* 397 * Bouncing might be required if the driver asks for an active 398 * exclusion region, a data alignment that is stricter than 1, and/or 399 * an active address boundary. 400 */ 401 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 402 403 /* Must bounce */ 404 struct bounce_zone *bz; 405 int maxpages; 406 407 if (dmat->bounce_zone == NULL) { 408 if ((error = alloc_bounce_zone(dmat)) != 0) 409 return (error); 410 } 411 bz = dmat->bounce_zone; 412 413 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 414 M_NOWAIT | M_ZERO); 415 if (*mapp == NULL) { 416 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 417 __func__, dmat, ENOMEM); 418 return (ENOMEM); 419 } 420 421 /* Initialize the new map */ 422 STAILQ_INIT(&((*mapp)->bpages)); 423 424 /* 425 * Attempt to add pages to our pool on a per-instance 426 * basis up to a sane limit. 427 */ 428 if (dmat->alignment > 1) 429 maxpages = MAX_BPAGES; 430 else 431 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 432 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 433 || (bz->map_count > 0 && bz->total_bpages < maxpages)) { 434 int pages; 435 436 pages = MAX(atop(dmat->maxsize), 1); 437 pages = MIN(maxpages - bz->total_bpages, pages); 438 pages = MAX(pages, 1); 439 if (alloc_bounce_pages(dmat, pages) < pages) 440 error = ENOMEM; 441 442 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 443 if (error == 0) 444 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 445 } else { 446 error = 0; 447 } 448 } 449 bz->map_count++; 450 } else { 451 *mapp = NULL; 452 } 453 if (error == 0) 454 dmat->map_count++; 455 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 456 __func__, dmat, dmat->flags, error); 457 return (error); 458 } 459 460 /* 461 * Destroy a handle for mapping from kva/uva/physical 462 * address space into bus device space. 463 */ 464 int 465 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 466 { 467 if (map != NULL && map != &nobounce_dmamap) { 468 if (STAILQ_FIRST(&map->bpages) != NULL) { 469 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 470 __func__, dmat, EBUSY); 471 return (EBUSY); 472 } 473 if (dmat->bounce_zone) 474 dmat->bounce_zone->map_count--; 475 free(map, M_DEVBUF); 476 } 477 dmat->map_count--; 478 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 479 return (0); 480 } 481 482 483 /* 484 * Allocate a piece of memory that can be efficiently mapped into 485 * bus device space based on the constraints lited in the dma tag. 486 * A dmamap to for use with dmamap_load is also allocated. 487 */ 488 int 489 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 490 bus_dmamap_t *mapp) 491 { 492 int mflags; 493 494 if (flags & BUS_DMA_NOWAIT) 495 mflags = M_NOWAIT; 496 else 497 mflags = M_WAITOK; 498 499 /* If we succeed, no mapping/bouncing will be required */ 500 *mapp = NULL; 501 502 if (dmat->segments == NULL) { 503 dmat->segments = (bus_dma_segment_t *)malloc( 504 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 505 mflags); 506 if (dmat->segments == NULL) { 507 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 508 __func__, dmat, dmat->flags, ENOMEM); 509 return (ENOMEM); 510 } 511 } 512 if (flags & BUS_DMA_ZERO) 513 mflags |= M_ZERO; 514 515 /* 516 * XXX: 517 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 518 * alignment guarantees of malloc need to be nailed down, and the 519 * code below should be rewritten to take that into account. 520 * 521 * In the meantime, we'll warn the user if malloc gets it wrong. 522 */ 523 if ((dmat->maxsize <= PAGE_SIZE) && 524 (dmat->alignment < dmat->maxsize) && 525 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 526 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 527 } else { 528 /* 529 * XXX Use Contigmalloc until it is merged into this facility 530 * and handles multi-seg allocations. Nobody is doing 531 * multi-seg allocations yet though. 532 * XXX Certain AGP hardware does. 533 */ 534 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 535 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 536 dmat->boundary); 537 } 538 if (*vaddr == NULL) { 539 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 540 __func__, dmat, dmat->flags, ENOMEM); 541 return (ENOMEM); 542 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 543 printf("bus_dmamem_alloc failed to align memory properly.\n"); 544 } 545 if (flags & BUS_DMA_NOCACHE) 546 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 547 PAT_UNCACHEABLE); 548 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 549 __func__, dmat, dmat->flags, 0); 550 return (0); 551 } 552 553 /* 554 * Free a piece of memory and it's allociated dmamap, that was allocated 555 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 556 */ 557 void 558 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 559 { 560 /* 561 * dmamem does not need to be bounced, so the map should be 562 * NULL 563 */ 564 if (map != NULL) 565 panic("bus_dmamem_free: Invalid map freed\n"); 566 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 567 if ((dmat->maxsize <= PAGE_SIZE) && 568 (dmat->alignment < dmat->maxsize) && 569 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 570 free(vaddr, M_DEVBUF); 571 else { 572 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 573 } 574 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 575 } 576 577 int 578 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap, 579 void *buf, bus_size_t buflen, int flags) 580 { 581 vm_offset_t vaddr; 582 vm_offset_t vendaddr; 583 bus_addr_t paddr; 584 585 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) { 586 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 587 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 588 dmat->boundary, dmat->alignment); 589 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 590 map, &nobounce_dmamap, map->pagesneeded); 591 /* 592 * Count the number of bounce pages 593 * needed in order to complete this transfer 594 */ 595 vaddr = (vm_offset_t)buf; 596 vendaddr = (vm_offset_t)buf + buflen; 597 598 while (vaddr < vendaddr) { 599 bus_size_t sg_len; 600 601 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK); 602 if (pmap) 603 paddr = pmap_extract(pmap, vaddr); 604 else 605 paddr = pmap_kextract(vaddr); 606 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 607 run_filter(dmat, paddr) != 0) { 608 sg_len = roundup2(sg_len, dmat->alignment); 609 map->pagesneeded++; 610 } 611 vaddr += sg_len; 612 } 613 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 614 } 615 616 /* Reserve Necessary Bounce Pages */ 617 if (map->pagesneeded != 0) { 618 mtx_lock(&bounce_lock); 619 if (flags & BUS_DMA_NOWAIT) { 620 if (reserve_bounce_pages(dmat, map, 0) != 0) { 621 mtx_unlock(&bounce_lock); 622 return (ENOMEM); 623 } 624 } else { 625 if (reserve_bounce_pages(dmat, map, 1) != 0) { 626 /* Queue us for resources */ 627 map->dmat = dmat; 628 map->buf = buf; 629 map->buflen = buflen; 630 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 631 map, links); 632 mtx_unlock(&bounce_lock); 633 return (EINPROGRESS); 634 } 635 } 636 mtx_unlock(&bounce_lock); 637 } 638 639 return (0); 640 } 641 642 /* 643 * Utility function to load a linear buffer. lastaddrp holds state 644 * between invocations (for multiple-buffer loads). segp contains 645 * the starting segment on entrace, and the ending segment on exit. 646 * first indicates if this is the first invocation of this function. 647 */ 648 static __inline int 649 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 650 bus_dmamap_t map, 651 void *buf, bus_size_t buflen, 652 pmap_t pmap, 653 int flags, 654 bus_addr_t *lastaddrp, 655 bus_dma_segment_t *segs, 656 int *segp, 657 int first) 658 { 659 bus_size_t sgsize; 660 bus_addr_t curaddr, lastaddr, baddr, bmask; 661 vm_offset_t vaddr; 662 int seg, error; 663 664 if (map == NULL) 665 map = &nobounce_dmamap; 666 667 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) { 668 error = _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags); 669 if (error) 670 return (error); 671 } 672 673 vaddr = (vm_offset_t)buf; 674 lastaddr = *lastaddrp; 675 bmask = ~(dmat->boundary - 1); 676 677 for (seg = *segp; buflen > 0 ; ) { 678 bus_size_t max_sgsize; 679 680 /* 681 * Get the physical address for this segment. 682 */ 683 if (pmap) 684 curaddr = pmap_extract(pmap, vaddr); 685 else 686 curaddr = pmap_kextract(vaddr); 687 688 /* 689 * Compute the segment size, and adjust counts. 690 */ 691 max_sgsize = MIN(buflen, dmat->maxsegsz); 692 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK); 693 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) && 694 map->pagesneeded != 0 && run_filter(dmat, curaddr)) { 695 sgsize = roundup2(sgsize, dmat->alignment); 696 sgsize = MIN(sgsize, max_sgsize); 697 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 698 } else { 699 sgsize = MIN(sgsize, max_sgsize); 700 } 701 702 /* 703 * Make sure we don't cross any boundaries. 704 */ 705 if (dmat->boundary > 0) { 706 baddr = (curaddr + dmat->boundary) & bmask; 707 if (sgsize > (baddr - curaddr)) 708 sgsize = (baddr - curaddr); 709 } 710 711 /* 712 * Insert chunk into a segment, coalescing with 713 * previous segment if possible. 714 */ 715 if (first) { 716 segs[seg].ds_addr = curaddr; 717 segs[seg].ds_len = sgsize; 718 first = 0; 719 } else { 720 if (curaddr == lastaddr && 721 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 722 (dmat->boundary == 0 || 723 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 724 segs[seg].ds_len += sgsize; 725 else { 726 if (++seg >= dmat->nsegments) 727 break; 728 segs[seg].ds_addr = curaddr; 729 segs[seg].ds_len = sgsize; 730 } 731 } 732 733 lastaddr = curaddr + sgsize; 734 vaddr += sgsize; 735 buflen -= sgsize; 736 } 737 738 *segp = seg; 739 *lastaddrp = lastaddr; 740 741 /* 742 * Did we fit? 743 */ 744 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 745 } 746 747 /* 748 * Map the buffer buf into bus space using the dmamap map. 749 */ 750 int 751 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 752 bus_size_t buflen, bus_dmamap_callback_t *callback, 753 void *callback_arg, int flags) 754 { 755 bus_addr_t lastaddr = 0; 756 int error, nsegs = 0; 757 758 if (map != NULL) { 759 flags |= BUS_DMA_WAITOK; 760 map->callback = callback; 761 map->callback_arg = callback_arg; 762 } 763 764 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 765 &lastaddr, dmat->segments, &nsegs, 1); 766 767 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 768 __func__, dmat, dmat->flags, error, nsegs + 1); 769 770 if (error == EINPROGRESS) { 771 return (error); 772 } 773 774 if (error) 775 (*callback)(callback_arg, dmat->segments, 0, error); 776 else 777 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 778 779 /* 780 * Return ENOMEM to the caller so that it can pass it up the stack. 781 * This error only happens when NOWAIT is set, so deferal is disabled. 782 */ 783 if (error == ENOMEM) 784 return (error); 785 786 return (0); 787 } 788 789 790 /* 791 * Like _bus_dmamap_load(), but for mbufs. 792 */ 793 static __inline int 794 _bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 795 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 796 int flags) 797 { 798 int error; 799 800 M_ASSERTPKTHDR(m0); 801 802 flags |= BUS_DMA_NOWAIT; 803 *nsegs = 0; 804 error = 0; 805 if (m0->m_pkthdr.len <= dmat->maxsize) { 806 int first = 1; 807 bus_addr_t lastaddr = 0; 808 struct mbuf *m; 809 810 for (m = m0; m != NULL && error == 0; m = m->m_next) { 811 if (m->m_len > 0) { 812 error = _bus_dmamap_load_buffer(dmat, map, 813 m->m_data, m->m_len, 814 NULL, flags, &lastaddr, 815 segs, nsegs, first); 816 first = 0; 817 } 818 } 819 } else { 820 error = EINVAL; 821 } 822 823 /* XXX FIXME: Having to increment nsegs is really annoying */ 824 ++*nsegs; 825 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 826 __func__, dmat, dmat->flags, error, *nsegs); 827 return (error); 828 } 829 830 int 831 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 832 struct mbuf *m0, 833 bus_dmamap_callback2_t *callback, void *callback_arg, 834 int flags) 835 { 836 int nsegs, error; 837 838 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs, 839 flags); 840 841 if (error) { 842 /* force "no valid mappings" in callback */ 843 (*callback)(callback_arg, dmat->segments, 0, 0, error); 844 } else { 845 (*callback)(callback_arg, dmat->segments, 846 nsegs, m0->m_pkthdr.len, error); 847 } 848 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 849 __func__, dmat, dmat->flags, error, nsegs); 850 return (error); 851 } 852 853 int 854 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 855 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 856 int flags) 857 { 858 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags)); 859 } 860 861 /* 862 * Like _bus_dmamap_load(), but for uios. 863 */ 864 int 865 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 866 struct uio *uio, 867 bus_dmamap_callback2_t *callback, void *callback_arg, 868 int flags) 869 { 870 bus_addr_t lastaddr; 871 int nsegs, error, first, i; 872 bus_size_t resid; 873 struct iovec *iov; 874 pmap_t pmap; 875 876 flags |= BUS_DMA_NOWAIT; 877 resid = uio->uio_resid; 878 iov = uio->uio_iov; 879 880 if (uio->uio_segflg == UIO_USERSPACE) { 881 KASSERT(uio->uio_td != NULL, 882 ("bus_dmamap_load_uio: USERSPACE but no proc")); 883 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 884 } else 885 pmap = NULL; 886 887 nsegs = 0; 888 error = 0; 889 first = 1; 890 lastaddr = (bus_addr_t) 0; 891 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 892 /* 893 * Now at the first iovec to load. Load each iovec 894 * until we have exhausted the residual count. 895 */ 896 bus_size_t minlen = 897 resid < iov[i].iov_len ? resid : iov[i].iov_len; 898 caddr_t addr = (caddr_t) iov[i].iov_base; 899 900 if (minlen > 0) { 901 error = _bus_dmamap_load_buffer(dmat, map, 902 addr, minlen, pmap, flags, &lastaddr, 903 dmat->segments, &nsegs, first); 904 first = 0; 905 906 resid -= minlen; 907 } 908 } 909 910 if (error) { 911 /* force "no valid mappings" in callback */ 912 (*callback)(callback_arg, dmat->segments, 0, 0, error); 913 } else { 914 (*callback)(callback_arg, dmat->segments, 915 nsegs+1, uio->uio_resid, error); 916 } 917 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 918 __func__, dmat, dmat->flags, error, nsegs + 1); 919 return (error); 920 } 921 922 /* 923 * Release the mapping held by map. 924 */ 925 void 926 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 927 { 928 struct bounce_page *bpage; 929 930 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 931 STAILQ_REMOVE_HEAD(&map->bpages, links); 932 free_bounce_page(dmat, bpage); 933 } 934 } 935 936 void 937 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 938 { 939 struct bounce_page *bpage; 940 941 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 942 /* 943 * Handle data bouncing. We might also 944 * want to add support for invalidating 945 * the caches on broken hardware 946 */ 947 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 948 "performing bounce", __func__, op, dmat, dmat->flags); 949 950 if (op & BUS_DMASYNC_PREWRITE) { 951 while (bpage != NULL) { 952 bcopy((void *)bpage->datavaddr, 953 (void *)bpage->vaddr, 954 bpage->datacount); 955 bpage = STAILQ_NEXT(bpage, links); 956 } 957 dmat->bounce_zone->total_bounced++; 958 } 959 960 if (op & BUS_DMASYNC_POSTREAD) { 961 while (bpage != NULL) { 962 bcopy((void *)bpage->vaddr, 963 (void *)bpage->datavaddr, 964 bpage->datacount); 965 bpage = STAILQ_NEXT(bpage, links); 966 } 967 dmat->bounce_zone->total_bounced++; 968 } 969 } 970 } 971 972 static void 973 init_bounce_pages(void *dummy __unused) 974 { 975 976 total_bpages = 0; 977 STAILQ_INIT(&bounce_zone_list); 978 STAILQ_INIT(&bounce_map_waitinglist); 979 STAILQ_INIT(&bounce_map_callbacklist); 980 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 981 } 982 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 983 984 static struct sysctl_ctx_list * 985 busdma_sysctl_tree(struct bounce_zone *bz) 986 { 987 return (&bz->sysctl_tree); 988 } 989 990 static struct sysctl_oid * 991 busdma_sysctl_tree_top(struct bounce_zone *bz) 992 { 993 return (bz->sysctl_tree_top); 994 } 995 996 static int 997 alloc_bounce_zone(bus_dma_tag_t dmat) 998 { 999 struct bounce_zone *bz; 1000 1001 /* Check to see if we already have a suitable zone */ 1002 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 1003 if ((dmat->alignment <= bz->alignment) 1004 && (dmat->lowaddr >= bz->lowaddr)) { 1005 dmat->bounce_zone = bz; 1006 return (0); 1007 } 1008 } 1009 1010 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 1011 M_NOWAIT | M_ZERO)) == NULL) 1012 return (ENOMEM); 1013 1014 STAILQ_INIT(&bz->bounce_page_list); 1015 bz->free_bpages = 0; 1016 bz->reserved_bpages = 0; 1017 bz->active_bpages = 0; 1018 bz->lowaddr = dmat->lowaddr; 1019 bz->alignment = MAX(dmat->alignment, PAGE_SIZE); 1020 bz->map_count = 0; 1021 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 1022 busdma_zonecount++; 1023 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 1024 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 1025 dmat->bounce_zone = bz; 1026 1027 sysctl_ctx_init(&bz->sysctl_tree); 1028 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 1029 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1030 CTLFLAG_RD, 0, ""); 1031 if (bz->sysctl_tree_top == NULL) { 1032 sysctl_ctx_free(&bz->sysctl_tree); 1033 return (0); /* XXX error code? */ 1034 } 1035 1036 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1037 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1038 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1039 "Total bounce pages"); 1040 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1041 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1042 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1043 "Free bounce pages"); 1044 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1045 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1046 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1047 "Reserved bounce pages"); 1048 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1049 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1050 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1051 "Active bounce pages"); 1052 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1053 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1054 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1055 "Total bounce requests"); 1056 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1057 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1058 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1059 "Total bounce requests that were deferred"); 1060 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1061 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1062 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1063 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1064 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1065 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1066 1067 return (0); 1068 } 1069 1070 static int 1071 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1072 { 1073 struct bounce_zone *bz; 1074 int count; 1075 1076 bz = dmat->bounce_zone; 1077 count = 0; 1078 while (numpages > 0) { 1079 struct bounce_page *bpage; 1080 1081 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1082 M_NOWAIT | M_ZERO); 1083 1084 if (bpage == NULL) 1085 break; 1086 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1087 M_NOWAIT, 0ul, 1088 bz->lowaddr, 1089 PAGE_SIZE, 1090 0); 1091 if (bpage->vaddr == 0) { 1092 free(bpage, M_DEVBUF); 1093 break; 1094 } 1095 bpage->busaddr = pmap_kextract(bpage->vaddr); 1096 mtx_lock(&bounce_lock); 1097 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1098 total_bpages++; 1099 bz->total_bpages++; 1100 bz->free_bpages++; 1101 mtx_unlock(&bounce_lock); 1102 count++; 1103 numpages--; 1104 } 1105 return (count); 1106 } 1107 1108 static int 1109 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1110 { 1111 struct bounce_zone *bz; 1112 int pages; 1113 1114 mtx_assert(&bounce_lock, MA_OWNED); 1115 bz = dmat->bounce_zone; 1116 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1117 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1118 return (map->pagesneeded - (map->pagesreserved + pages)); 1119 bz->free_bpages -= pages; 1120 bz->reserved_bpages += pages; 1121 map->pagesreserved += pages; 1122 pages = map->pagesneeded - map->pagesreserved; 1123 1124 return (pages); 1125 } 1126 1127 static bus_addr_t 1128 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1129 bus_size_t size) 1130 { 1131 struct bounce_zone *bz; 1132 struct bounce_page *bpage; 1133 1134 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1135 KASSERT(map != NULL && map != &nobounce_dmamap, 1136 ("add_bounce_page: bad map %p", map)); 1137 1138 bz = dmat->bounce_zone; 1139 if (map->pagesneeded == 0) 1140 panic("add_bounce_page: map doesn't need any pages"); 1141 map->pagesneeded--; 1142 1143 if (map->pagesreserved == 0) 1144 panic("add_bounce_page: map doesn't need any pages"); 1145 map->pagesreserved--; 1146 1147 mtx_lock(&bounce_lock); 1148 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1149 if (bpage == NULL) 1150 panic("add_bounce_page: free page list is empty"); 1151 1152 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1153 bz->reserved_bpages--; 1154 bz->active_bpages++; 1155 mtx_unlock(&bounce_lock); 1156 1157 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1158 /* Page offset needs to be preserved. */ 1159 bpage->vaddr |= vaddr & PAGE_MASK; 1160 bpage->busaddr |= vaddr & PAGE_MASK; 1161 } 1162 bpage->datavaddr = vaddr; 1163 bpage->datacount = size; 1164 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1165 return (bpage->busaddr); 1166 } 1167 1168 static void 1169 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1170 { 1171 struct bus_dmamap *map; 1172 struct bounce_zone *bz; 1173 1174 bz = dmat->bounce_zone; 1175 bpage->datavaddr = 0; 1176 bpage->datacount = 0; 1177 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) { 1178 /* 1179 * Reset the bounce page to start at offset 0. Other uses 1180 * of this bounce page may need to store a full page of 1181 * data and/or assume it starts on a page boundary. 1182 */ 1183 bpage->vaddr &= ~PAGE_MASK; 1184 bpage->busaddr &= ~PAGE_MASK; 1185 } 1186 1187 mtx_lock(&bounce_lock); 1188 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1189 bz->free_bpages++; 1190 bz->active_bpages--; 1191 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1192 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1193 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1194 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1195 map, links); 1196 busdma_swi_pending = 1; 1197 bz->total_deferred++; 1198 swi_sched(vm_ih, 0); 1199 } 1200 } 1201 mtx_unlock(&bounce_lock); 1202 } 1203 1204 void 1205 busdma_swi(void) 1206 { 1207 bus_dma_tag_t dmat; 1208 struct bus_dmamap *map; 1209 1210 mtx_lock(&bounce_lock); 1211 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1212 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1213 mtx_unlock(&bounce_lock); 1214 dmat = map->dmat; 1215 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1216 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1217 map->callback, map->callback_arg, /*flags*/0); 1218 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1219 mtx_lock(&bounce_lock); 1220 } 1221 mtx_unlock(&bounce_lock); 1222 }
Cache object: 82fd938b6bd61307659b10ea761b69b0
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