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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/6.3/sys/i386/i386/busdma_machdep.c 173886 2007-11-24 19:45:58Z cvs2svn $"); 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 58 struct bounce_zone; 59 60 struct bus_dma_tag { 61 bus_dma_tag_t parent; 62 bus_size_t alignment; 63 bus_size_t boundary; 64 bus_addr_t lowaddr; 65 bus_addr_t highaddr; 66 bus_dma_filter_t *filter; 67 void *filterarg; 68 bus_size_t maxsize; 69 u_int nsegments; 70 bus_size_t maxsegsz; 71 int flags; 72 int ref_count; 73 int map_count; 74 bus_dma_lock_t *lockfunc; 75 void *lockfuncarg; 76 bus_dma_segment_t *segments; 77 struct bounce_zone *bounce_zone; 78 }; 79 80 struct bounce_page { 81 vm_offset_t vaddr; /* kva of bounce buffer */ 82 bus_addr_t busaddr; /* Physical address */ 83 vm_offset_t datavaddr; /* kva of client data */ 84 bus_size_t datacount; /* client data count */ 85 STAILQ_ENTRY(bounce_page) links; 86 }; 87 88 int busdma_swi_pending; 89 90 struct bounce_zone { 91 STAILQ_ENTRY(bounce_zone) links; 92 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list; 93 int total_bpages; 94 int free_bpages; 95 int reserved_bpages; 96 int active_bpages; 97 int total_bounced; 98 int total_deferred; 99 bus_size_t alignment; 100 bus_size_t boundary; 101 bus_addr_t lowaddr; 102 char zoneid[8]; 103 char lowaddrid[20]; 104 struct sysctl_ctx_list sysctl_tree; 105 struct sysctl_oid *sysctl_tree_top; 106 }; 107 108 static struct mtx bounce_lock; 109 static int total_bpages; 110 static int busdma_zonecount; 111 static STAILQ_HEAD(, bounce_zone) bounce_zone_list; 112 113 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters"); 114 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0, 115 "Total bounce pages"); 116 117 struct bus_dmamap { 118 struct bp_list bpages; 119 int pagesneeded; 120 int pagesreserved; 121 bus_dma_tag_t dmat; 122 void *buf; /* unmapped buffer pointer */ 123 bus_size_t buflen; /* unmapped buffer length */ 124 bus_dmamap_callback_t *callback; 125 void *callback_arg; 126 STAILQ_ENTRY(bus_dmamap) links; 127 }; 128 129 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist; 130 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist; 131 static struct bus_dmamap nobounce_dmamap; 132 133 static void init_bounce_pages(void *dummy); 134 static int alloc_bounce_zone(bus_dma_tag_t dmat); 135 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages); 136 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, 137 int commit); 138 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, 139 vm_offset_t vaddr, bus_size_t size); 140 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage); 141 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr); 142 143 /* 144 * Return true if a match is made. 145 * 146 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'. 147 * 148 * If paddr is within the bounds of the dma tag then call the filter callback 149 * to check for a match, if there is no filter callback then assume a match. 150 */ 151 static __inline int 152 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr) 153 { 154 int retval; 155 156 retval = 0; 157 158 do { 159 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) 160 || ((paddr & (dmat->alignment - 1)) != 0)) 161 && (dmat->filter == NULL 162 || (*dmat->filter)(dmat->filterarg, paddr) != 0)) 163 retval = 1; 164 165 dmat = dmat->parent; 166 } while (retval == 0 && dmat != NULL); 167 return (retval); 168 } 169 170 /* 171 * Convenience function for manipulating driver locks from busdma (during 172 * busdma_swi, for example). Drivers that don't provide their own locks 173 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own 174 * non-mutex locking scheme don't have to use this at all. 175 */ 176 void 177 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op) 178 { 179 struct mtx *dmtx; 180 181 dmtx = (struct mtx *)arg; 182 switch (op) { 183 case BUS_DMA_LOCK: 184 mtx_lock(dmtx); 185 break; 186 case BUS_DMA_UNLOCK: 187 mtx_unlock(dmtx); 188 break; 189 default: 190 panic("Unknown operation 0x%x for busdma_lock_mutex!", op); 191 } 192 } 193 194 /* 195 * dflt_lock should never get called. It gets put into the dma tag when 196 * lockfunc == NULL, which is only valid if the maps that are associated 197 * with the tag are meant to never be defered. 198 * XXX Should have a way to identify which driver is responsible here. 199 */ 200 static void 201 dflt_lock(void *arg, bus_dma_lock_op_t op) 202 { 203 panic("driver error: busdma dflt_lock called"); 204 } 205 206 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3 207 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4 208 /* 209 * Allocate a device specific dma_tag. 210 */ 211 int 212 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 213 bus_size_t boundary, bus_addr_t lowaddr, 214 bus_addr_t highaddr, bus_dma_filter_t *filter, 215 void *filterarg, bus_size_t maxsize, int nsegments, 216 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, 217 void *lockfuncarg, bus_dma_tag_t *dmat) 218 { 219 bus_dma_tag_t newtag; 220 int error = 0; 221 222 /* Basic sanity checking */ 223 if (boundary != 0 && boundary < maxsegsz) 224 maxsegsz = boundary; 225 226 /* Return a NULL tag on failure */ 227 *dmat = NULL; 228 229 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, 230 M_ZERO | M_NOWAIT); 231 if (newtag == NULL) { 232 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 233 __func__, newtag, 0, error); 234 return (ENOMEM); 235 } 236 237 newtag->parent = parent; 238 newtag->alignment = alignment; 239 newtag->boundary = boundary; 240 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1); 241 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + 242 (PAGE_SIZE - 1); 243 newtag->filter = filter; 244 newtag->filterarg = filterarg; 245 newtag->maxsize = maxsize; 246 newtag->nsegments = nsegments; 247 newtag->maxsegsz = maxsegsz; 248 newtag->flags = flags; 249 newtag->ref_count = 1; /* Count ourself */ 250 newtag->map_count = 0; 251 if (lockfunc != NULL) { 252 newtag->lockfunc = lockfunc; 253 newtag->lockfuncarg = lockfuncarg; 254 } else { 255 newtag->lockfunc = dflt_lock; 256 newtag->lockfuncarg = NULL; 257 } 258 newtag->segments = NULL; 259 260 /* Take into account any restrictions imposed by our parent tag */ 261 if (parent != NULL) { 262 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr); 263 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr); 264 if (newtag->boundary == 0) 265 newtag->boundary = parent->boundary; 266 else if (parent->boundary != 0) 267 newtag->boundary = MIN(parent->boundary, 268 newtag->boundary); 269 if (newtag->filter == NULL) { 270 /* 271 * Short circuit looking at our parent directly 272 * since we have encapsulated all of its information 273 */ 274 newtag->filter = parent->filter; 275 newtag->filterarg = parent->filterarg; 276 newtag->parent = parent->parent; 277 } 278 if (newtag->parent != NULL) 279 atomic_add_int(&parent->ref_count, 1); 280 } 281 282 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) 283 || newtag->alignment > 1) 284 newtag->flags |= BUS_DMA_COULD_BOUNCE; 285 286 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) && 287 (flags & BUS_DMA_ALLOCNOW) != 0) { 288 struct bounce_zone *bz; 289 290 /* Must bounce */ 291 292 if ((error = alloc_bounce_zone(newtag)) != 0) { 293 free(newtag, M_DEVBUF); 294 return (error); 295 } 296 bz = newtag->bounce_zone; 297 298 if (ptoa(bz->total_bpages) < maxsize) { 299 int pages; 300 301 pages = atop(maxsize) - bz->total_bpages; 302 303 /* Add pages to our bounce pool */ 304 if (alloc_bounce_pages(newtag, pages) < pages) 305 error = ENOMEM; 306 } 307 /* Performed initial allocation */ 308 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP; 309 } 310 311 if (error != 0) { 312 free(newtag, M_DEVBUF); 313 } else { 314 *dmat = newtag; 315 } 316 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", 317 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error); 318 return (error); 319 } 320 321 int 322 bus_dma_tag_destroy(bus_dma_tag_t dmat) 323 { 324 bus_dma_tag_t dmat_copy; 325 int error; 326 327 error = 0; 328 dmat_copy = dmat; 329 330 if (dmat != NULL) { 331 332 if (dmat->map_count != 0) { 333 error = EBUSY; 334 goto out; 335 } 336 337 while (dmat != NULL) { 338 bus_dma_tag_t parent; 339 340 parent = dmat->parent; 341 atomic_subtract_int(&dmat->ref_count, 1); 342 if (dmat->ref_count == 0) { 343 if (dmat->segments != NULL) 344 free(dmat->segments, M_DEVBUF); 345 free(dmat, M_DEVBUF); 346 /* 347 * Last reference count, so 348 * release our reference 349 * count on our parent. 350 */ 351 dmat = parent; 352 } else 353 dmat = NULL; 354 } 355 } 356 out: 357 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); 358 return (error); 359 } 360 361 /* 362 * Allocate a handle for mapping from kva/uva/physical 363 * address space into bus device space. 364 */ 365 int 366 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) 367 { 368 int error; 369 370 error = 0; 371 372 if (dmat->segments == NULL) { 373 dmat->segments = (bus_dma_segment_t *)malloc( 374 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 375 M_NOWAIT); 376 if (dmat->segments == NULL) { 377 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 378 __func__, dmat, ENOMEM); 379 return (ENOMEM); 380 } 381 } 382 383 /* 384 * Bouncing might be required if the driver asks for an active 385 * exclusion region, a data alignment that is stricter than 1, and/or 386 * an active address boundary. 387 */ 388 if (dmat->flags & BUS_DMA_COULD_BOUNCE) { 389 390 /* Must bounce */ 391 struct bounce_zone *bz; 392 int maxpages; 393 394 if (dmat->bounce_zone == NULL) { 395 if ((error = alloc_bounce_zone(dmat)) != 0) 396 return (error); 397 } 398 bz = dmat->bounce_zone; 399 400 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF, 401 M_NOWAIT | M_ZERO); 402 if (*mapp == NULL) { 403 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 404 __func__, dmat, ENOMEM); 405 return (ENOMEM); 406 } 407 408 /* Initialize the new map */ 409 STAILQ_INIT(&((*mapp)->bpages)); 410 411 /* 412 * Attempt to add pages to our pool on a per-instance 413 * basis up to a sane limit. 414 */ 415 if (dmat->alignment > 1) 416 maxpages = MAX_BPAGES; 417 else 418 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr)); 419 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 420 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) { 421 int pages; 422 423 pages = MAX(atop(dmat->maxsize), 1); 424 pages = MIN(maxpages - bz->total_bpages, pages); 425 pages = MAX(pages, 1); 426 if (alloc_bounce_pages(dmat, pages) < pages) 427 error = ENOMEM; 428 429 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) { 430 if (error == 0) 431 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP; 432 } else { 433 error = 0; 434 } 435 } 436 } else { 437 *mapp = NULL; 438 } 439 if (error == 0) 440 dmat->map_count++; 441 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 442 __func__, dmat, dmat->flags, error); 443 return (error); 444 } 445 446 /* 447 * Destroy a handle for mapping from kva/uva/physical 448 * address space into bus device space. 449 */ 450 int 451 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map) 452 { 453 if (map != NULL && map != &nobounce_dmamap) { 454 if (STAILQ_FIRST(&map->bpages) != NULL) { 455 CTR3(KTR_BUSDMA, "%s: tag %p error %d", 456 __func__, dmat, EBUSY); 457 return (EBUSY); 458 } 459 free(map, M_DEVBUF); 460 } 461 dmat->map_count--; 462 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat); 463 return (0); 464 } 465 466 467 /* 468 * Allocate a piece of memory that can be efficiently mapped into 469 * bus device space based on the constraints lited in the dma tag. 470 * A dmamap to for use with dmamap_load is also allocated. 471 */ 472 int 473 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 474 bus_dmamap_t *mapp) 475 { 476 int mflags; 477 478 if (flags & BUS_DMA_NOWAIT) 479 mflags = M_NOWAIT; 480 else 481 mflags = M_WAITOK; 482 if (flags & BUS_DMA_ZERO) 483 mflags |= M_ZERO; 484 485 /* If we succeed, no mapping/bouncing will be required */ 486 *mapp = NULL; 487 488 if (dmat->segments == NULL) { 489 dmat->segments = (bus_dma_segment_t *)malloc( 490 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF, 491 M_NOWAIT); 492 if (dmat->segments == NULL) { 493 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 494 __func__, dmat, dmat->flags, ENOMEM); 495 return (ENOMEM); 496 } 497 } 498 499 /* 500 * XXX: 501 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact 502 * alignment guarantees of malloc need to be nailed down, and the 503 * code below should be rewritten to take that into account. 504 * 505 * In the meantime, we'll warn the user if malloc gets it wrong. 506 */ 507 if ((dmat->maxsize <= PAGE_SIZE) && 508 (dmat->alignment < dmat->maxsize) && 509 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) { 510 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags); 511 } else { 512 /* 513 * XXX Use Contigmalloc until it is merged into this facility 514 * and handles multi-seg allocations. Nobody is doing 515 * multi-seg allocations yet though. 516 * XXX Certain AGP hardware does. 517 */ 518 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags, 519 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul, 520 dmat->boundary); 521 } 522 if (*vaddr == NULL) { 523 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 524 __func__, dmat, dmat->flags, ENOMEM); 525 return (ENOMEM); 526 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) { 527 printf("bus_dmamem_alloc failed to align memory properly.\n"); 528 } 529 if (flags & BUS_DMA_NOCACHE) 530 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize, 531 PAT_UNCACHEABLE); 532 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d", 533 __func__, dmat, dmat->flags, ENOMEM); 534 return (0); 535 } 536 537 /* 538 * Free a piece of memory and it's allociated dmamap, that was allocated 539 * via bus_dmamem_alloc. Make the same choice for free/contigfree. 540 */ 541 void 542 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map) 543 { 544 /* 545 * dmamem does not need to be bounced, so the map should be 546 * NULL 547 */ 548 if (map != NULL) 549 panic("bus_dmamem_free: Invalid map freed\n"); 550 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK); 551 if ((dmat->maxsize <= PAGE_SIZE) && 552 (dmat->alignment < dmat->maxsize) && 553 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) 554 free(vaddr, M_DEVBUF); 555 else { 556 contigfree(vaddr, dmat->maxsize, M_DEVBUF); 557 } 558 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags); 559 } 560 561 /* 562 * Utility function to load a linear buffer. lastaddrp holds state 563 * between invocations (for multiple-buffer loads). segp contains 564 * the starting segment on entrace, and the ending segment on exit. 565 * first indicates if this is the first invocation of this function. 566 */ 567 static __inline int 568 _bus_dmamap_load_buffer(bus_dma_tag_t dmat, 569 bus_dmamap_t map, 570 void *buf, bus_size_t buflen, 571 pmap_t pmap, 572 int flags, 573 bus_addr_t *lastaddrp, 574 bus_dma_segment_t *segs, 575 int *segp, 576 int first) 577 { 578 bus_size_t sgsize; 579 bus_addr_t curaddr, lastaddr, baddr, bmask; 580 vm_offset_t vaddr; 581 bus_addr_t paddr; 582 int needbounce = 0; 583 int seg; 584 585 if (map == NULL) 586 map = &nobounce_dmamap; 587 588 if ((map != &nobounce_dmamap && map->pagesneeded == 0) 589 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) { 590 vm_offset_t vendaddr; 591 592 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, " 593 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem), 594 dmat->boundary, dmat->alignment); 595 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d", 596 map, &nobounce_dmamap, map->pagesneeded); 597 /* 598 * Count the number of bounce pages 599 * needed in order to complete this transfer 600 */ 601 vaddr = trunc_page((vm_offset_t)buf); 602 vendaddr = (vm_offset_t)buf + buflen; 603 604 while (vaddr < vendaddr) { 605 paddr = pmap_kextract(vaddr); 606 if (run_filter(dmat, paddr) != 0) { 607 needbounce = 1; 608 map->pagesneeded++; 609 } 610 vaddr += PAGE_SIZE; 611 } 612 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded); 613 } 614 615 /* Reserve Necessary Bounce Pages */ 616 if (map->pagesneeded != 0) { 617 mtx_lock(&bounce_lock); 618 if (flags & BUS_DMA_NOWAIT) { 619 if (reserve_bounce_pages(dmat, map, 0) != 0) { 620 mtx_unlock(&bounce_lock); 621 return (ENOMEM); 622 } 623 } else { 624 if (reserve_bounce_pages(dmat, map, 1) != 0) { 625 /* Queue us for resources */ 626 map->dmat = dmat; 627 map->buf = buf; 628 map->buflen = buflen; 629 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, 630 map, links); 631 mtx_unlock(&bounce_lock); 632 return (EINPROGRESS); 633 } 634 } 635 mtx_unlock(&bounce_lock); 636 } 637 638 vaddr = (vm_offset_t)buf; 639 lastaddr = *lastaddrp; 640 bmask = ~(dmat->boundary - 1); 641 642 for (seg = *segp; buflen > 0 ; ) { 643 /* 644 * Get the physical address for this segment. 645 */ 646 if (pmap) 647 curaddr = pmap_extract(pmap, vaddr); 648 else 649 curaddr = pmap_kextract(vaddr); 650 651 /* 652 * Compute the segment size, and adjust counts. 653 */ 654 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK); 655 if (buflen < sgsize) 656 sgsize = buflen; 657 658 /* 659 * Make sure we don't cross any boundaries. 660 */ 661 if (dmat->boundary > 0) { 662 baddr = (curaddr + dmat->boundary) & bmask; 663 if (sgsize > (baddr - curaddr)) 664 sgsize = (baddr - curaddr); 665 } 666 667 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) 668 curaddr = add_bounce_page(dmat, map, vaddr, sgsize); 669 670 /* 671 * Insert chunk into a segment, coalescing with 672 * previous segment if possible. 673 */ 674 if (first) { 675 segs[seg].ds_addr = curaddr; 676 segs[seg].ds_len = sgsize; 677 first = 0; 678 } else { 679 if (needbounce == 0 && curaddr == lastaddr && 680 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz && 681 (dmat->boundary == 0 || 682 (segs[seg].ds_addr & bmask) == (curaddr & bmask))) 683 segs[seg].ds_len += sgsize; 684 else { 685 if (++seg >= dmat->nsegments) 686 break; 687 segs[seg].ds_addr = curaddr; 688 segs[seg].ds_len = sgsize; 689 } 690 } 691 692 lastaddr = curaddr + sgsize; 693 vaddr += sgsize; 694 buflen -= sgsize; 695 } 696 697 *segp = seg; 698 *lastaddrp = lastaddr; 699 700 /* 701 * Did we fit? 702 */ 703 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */ 704 } 705 706 /* 707 * Map the buffer buf into bus space using the dmamap map. 708 */ 709 int 710 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 711 bus_size_t buflen, bus_dmamap_callback_t *callback, 712 void *callback_arg, int flags) 713 { 714 bus_addr_t lastaddr = 0; 715 int error, nsegs = 0; 716 717 if (map != NULL) { 718 flags |= BUS_DMA_WAITOK; 719 map->callback = callback; 720 map->callback_arg = callback_arg; 721 } 722 723 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags, 724 &lastaddr, dmat->segments, &nsegs, 1); 725 726 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 727 __func__, dmat, dmat->flags, error, nsegs + 1); 728 729 if (error == EINPROGRESS) { 730 return (error); 731 } 732 733 if (error) 734 (*callback)(callback_arg, dmat->segments, 0, error); 735 else 736 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0); 737 738 /* 739 * Return ENOMEM to the caller so that it can pass it up the stack. 740 * This error only happens when NOWAIT is set, so deferal is disabled. 741 */ 742 if (error == ENOMEM) 743 return (error); 744 745 return (0); 746 } 747 748 749 /* 750 * Like _bus_dmamap_load(), but for mbufs. 751 */ 752 int 753 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 754 struct mbuf *m0, 755 bus_dmamap_callback2_t *callback, void *callback_arg, 756 int flags) 757 { 758 int nsegs, error; 759 760 M_ASSERTPKTHDR(m0); 761 762 flags |= BUS_DMA_NOWAIT; 763 nsegs = 0; 764 error = 0; 765 if (m0->m_pkthdr.len <= dmat->maxsize) { 766 int first = 1; 767 bus_addr_t lastaddr = 0; 768 struct mbuf *m; 769 770 for (m = m0; m != NULL && error == 0; m = m->m_next) { 771 if (m->m_len > 0) { 772 error = _bus_dmamap_load_buffer(dmat, map, 773 m->m_data, m->m_len, 774 NULL, flags, &lastaddr, 775 dmat->segments, &nsegs, first); 776 first = 0; 777 } 778 } 779 } else { 780 error = EINVAL; 781 } 782 783 if (error) { 784 /* force "no valid mappings" in callback */ 785 (*callback)(callback_arg, dmat->segments, 0, 0, error); 786 } else { 787 (*callback)(callback_arg, dmat->segments, 788 nsegs+1, m0->m_pkthdr.len, error); 789 } 790 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 791 __func__, dmat, dmat->flags, error, nsegs + 1); 792 return (error); 793 } 794 795 int 796 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, 797 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, 798 int flags) 799 { 800 int error; 801 802 M_ASSERTPKTHDR(m0); 803 804 flags |= BUS_DMA_NOWAIT; 805 *nsegs = 0; 806 error = 0; 807 if (m0->m_pkthdr.len <= dmat->maxsize) { 808 int first = 1; 809 bus_addr_t lastaddr = 0; 810 struct mbuf *m; 811 812 for (m = m0; m != NULL && error == 0; m = m->m_next) { 813 if (m->m_len > 0) { 814 error = _bus_dmamap_load_buffer(dmat, map, 815 m->m_data, m->m_len, 816 NULL, flags, &lastaddr, 817 segs, nsegs, first); 818 first = 0; 819 } 820 } 821 } else { 822 error = EINVAL; 823 } 824 825 /* XXX FIXME: Having to increment nsegs is really annoying */ 826 ++*nsegs; 827 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 828 __func__, dmat, dmat->flags, error, *nsegs); 829 return (error); 830 } 831 832 /* 833 * Like _bus_dmamap_load(), but for uios. 834 */ 835 int 836 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 837 struct uio *uio, 838 bus_dmamap_callback2_t *callback, void *callback_arg, 839 int flags) 840 { 841 bus_addr_t lastaddr; 842 int nsegs, error, first, i; 843 bus_size_t resid; 844 struct iovec *iov; 845 pmap_t pmap; 846 847 flags |= BUS_DMA_NOWAIT; 848 resid = uio->uio_resid; 849 iov = uio->uio_iov; 850 851 if (uio->uio_segflg == UIO_USERSPACE) { 852 KASSERT(uio->uio_td != NULL, 853 ("bus_dmamap_load_uio: USERSPACE but no proc")); 854 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); 855 } else 856 pmap = NULL; 857 858 nsegs = 0; 859 error = 0; 860 first = 1; 861 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) { 862 /* 863 * Now at the first iovec to load. Load each iovec 864 * until we have exhausted the residual count. 865 */ 866 bus_size_t minlen = 867 resid < iov[i].iov_len ? resid : iov[i].iov_len; 868 caddr_t addr = (caddr_t) iov[i].iov_base; 869 870 if (minlen > 0) { 871 error = _bus_dmamap_load_buffer(dmat, map, 872 addr, minlen, pmap, flags, &lastaddr, 873 dmat->segments, &nsegs, first); 874 first = 0; 875 876 resid -= minlen; 877 } 878 } 879 880 if (error) { 881 /* force "no valid mappings" in callback */ 882 (*callback)(callback_arg, dmat->segments, 0, 0, error); 883 } else { 884 (*callback)(callback_arg, dmat->segments, 885 nsegs+1, uio->uio_resid, error); 886 } 887 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d", 888 __func__, dmat, dmat->flags, error, nsegs + 1); 889 return (error); 890 } 891 892 /* 893 * Release the mapping held by map. 894 */ 895 void 896 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map) 897 { 898 struct bounce_page *bpage; 899 900 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 901 STAILQ_REMOVE_HEAD(&map->bpages, links); 902 free_bounce_page(dmat, bpage); 903 } 904 } 905 906 void 907 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op) 908 { 909 struct bounce_page *bpage; 910 911 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) { 912 /* 913 * Handle data bouncing. We might also 914 * want to add support for invalidating 915 * the caches on broken hardware 916 */ 917 dmat->bounce_zone->total_bounced++; 918 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x " 919 "performing bounce", __func__, op, dmat, dmat->flags); 920 921 if (op & BUS_DMASYNC_PREWRITE) { 922 while (bpage != NULL) { 923 bcopy((void *)bpage->datavaddr, 924 (void *)bpage->vaddr, 925 bpage->datacount); 926 bpage = STAILQ_NEXT(bpage, links); 927 } 928 } 929 930 if (op & BUS_DMASYNC_POSTREAD) { 931 while (bpage != NULL) { 932 bcopy((void *)bpage->vaddr, 933 (void *)bpage->datavaddr, 934 bpage->datacount); 935 bpage = STAILQ_NEXT(bpage, links); 936 } 937 } 938 } 939 } 940 941 static void 942 init_bounce_pages(void *dummy __unused) 943 { 944 945 total_bpages = 0; 946 STAILQ_INIT(&bounce_zone_list); 947 STAILQ_INIT(&bounce_map_waitinglist); 948 STAILQ_INIT(&bounce_map_callbacklist); 949 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF); 950 } 951 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL); 952 953 static struct sysctl_ctx_list * 954 busdma_sysctl_tree(struct bounce_zone *bz) 955 { 956 return (&bz->sysctl_tree); 957 } 958 959 static struct sysctl_oid * 960 busdma_sysctl_tree_top(struct bounce_zone *bz) 961 { 962 return (bz->sysctl_tree_top); 963 } 964 965 static int 966 alloc_bounce_zone(bus_dma_tag_t dmat) 967 { 968 struct bounce_zone *bz; 969 970 /* Check to see if we already have a suitable zone */ 971 STAILQ_FOREACH(bz, &bounce_zone_list, links) { 972 if ((dmat->alignment <= bz->alignment) 973 && (dmat->boundary <= bz->boundary) 974 && (dmat->lowaddr >= bz->lowaddr)) { 975 dmat->bounce_zone = bz; 976 return (0); 977 } 978 } 979 980 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF, 981 M_NOWAIT | M_ZERO)) == NULL) 982 return (ENOMEM); 983 984 STAILQ_INIT(&bz->bounce_page_list); 985 bz->free_bpages = 0; 986 bz->reserved_bpages = 0; 987 bz->active_bpages = 0; 988 bz->lowaddr = dmat->lowaddr; 989 bz->alignment = dmat->alignment; 990 bz->boundary = dmat->boundary; 991 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount); 992 busdma_zonecount++; 993 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr); 994 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links); 995 dmat->bounce_zone = bz; 996 997 sysctl_ctx_init(&bz->sysctl_tree); 998 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree, 999 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid, 1000 CTLFLAG_RD, 0, ""); 1001 if (bz->sysctl_tree_top == NULL) { 1002 sysctl_ctx_free(&bz->sysctl_tree); 1003 return (0); /* XXX error code? */ 1004 } 1005 1006 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1007 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1008 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0, 1009 "Total bounce pages"); 1010 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1011 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1012 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0, 1013 "Free bounce pages"); 1014 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1016 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0, 1017 "Reserved bounce pages"); 1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1020 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0, 1021 "Active bounce pages"); 1022 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1023 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1024 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0, 1025 "Total bounce requests"); 1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1028 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0, 1029 "Total bounce requests that were deferred"); 1030 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz), 1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1032 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, ""); 1033 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1034 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1035 "alignment", CTLFLAG_RD, &bz->alignment, 0, ""); 1036 SYSCTL_ADD_INT(busdma_sysctl_tree(bz), 1037 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO, 1038 "boundary", CTLFLAG_RD, &bz->boundary, 0, ""); 1039 1040 return (0); 1041 } 1042 1043 static int 1044 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages) 1045 { 1046 struct bounce_zone *bz; 1047 int count; 1048 1049 bz = dmat->bounce_zone; 1050 count = 0; 1051 while (numpages > 0) { 1052 struct bounce_page *bpage; 1053 1054 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF, 1055 M_NOWAIT | M_ZERO); 1056 1057 if (bpage == NULL) 1058 break; 1059 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF, 1060 M_NOWAIT, 0ul, 1061 bz->lowaddr, 1062 PAGE_SIZE, 1063 bz->boundary); 1064 if (bpage->vaddr == 0) { 1065 free(bpage, M_DEVBUF); 1066 break; 1067 } 1068 bpage->busaddr = pmap_kextract(bpage->vaddr); 1069 mtx_lock(&bounce_lock); 1070 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links); 1071 total_bpages++; 1072 bz->total_bpages++; 1073 bz->free_bpages++; 1074 mtx_unlock(&bounce_lock); 1075 count++; 1076 numpages--; 1077 } 1078 return (count); 1079 } 1080 1081 static int 1082 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit) 1083 { 1084 struct bounce_zone *bz; 1085 int pages; 1086 1087 mtx_assert(&bounce_lock, MA_OWNED); 1088 bz = dmat->bounce_zone; 1089 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved); 1090 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages)) 1091 return (map->pagesneeded - (map->pagesreserved + pages)); 1092 bz->free_bpages -= pages; 1093 bz->reserved_bpages += pages; 1094 map->pagesreserved += pages; 1095 pages = map->pagesneeded - map->pagesreserved; 1096 1097 return (pages); 1098 } 1099 1100 static bus_addr_t 1101 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr, 1102 bus_size_t size) 1103 { 1104 struct bounce_zone *bz; 1105 struct bounce_page *bpage; 1106 1107 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag")); 1108 KASSERT(map != NULL && map != &nobounce_dmamap, 1109 ("add_bounce_page: bad map %p", map)); 1110 1111 bz = dmat->bounce_zone; 1112 if (map->pagesneeded == 0) 1113 panic("add_bounce_page: map doesn't need any pages"); 1114 map->pagesneeded--; 1115 1116 if (map->pagesreserved == 0) 1117 panic("add_bounce_page: map doesn't need any pages"); 1118 map->pagesreserved--; 1119 1120 mtx_lock(&bounce_lock); 1121 bpage = STAILQ_FIRST(&bz->bounce_page_list); 1122 if (bpage == NULL) 1123 panic("add_bounce_page: free page list is empty"); 1124 1125 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links); 1126 bz->reserved_bpages--; 1127 bz->active_bpages++; 1128 mtx_unlock(&bounce_lock); 1129 1130 bpage->datavaddr = vaddr; 1131 bpage->datacount = size; 1132 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links); 1133 return (bpage->busaddr); 1134 } 1135 1136 static void 1137 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage) 1138 { 1139 struct bus_dmamap *map; 1140 struct bounce_zone *bz; 1141 1142 bz = dmat->bounce_zone; 1143 bpage->datavaddr = 0; 1144 bpage->datacount = 0; 1145 1146 mtx_lock(&bounce_lock); 1147 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links); 1148 bz->free_bpages++; 1149 bz->active_bpages--; 1150 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) { 1151 if (reserve_bounce_pages(map->dmat, map, 1) == 0) { 1152 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links); 1153 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, 1154 map, links); 1155 busdma_swi_pending = 1; 1156 bz->total_deferred++; 1157 swi_sched(vm_ih, 0); 1158 } 1159 } 1160 mtx_unlock(&bounce_lock); 1161 } 1162 1163 void 1164 busdma_swi(void) 1165 { 1166 bus_dma_tag_t dmat; 1167 struct bus_dmamap *map; 1168 1169 mtx_lock(&bounce_lock); 1170 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) { 1171 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links); 1172 mtx_unlock(&bounce_lock); 1173 dmat = map->dmat; 1174 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK); 1175 bus_dmamap_load(map->dmat, map, map->buf, map->buflen, 1176 map->callback, map->callback_arg, /*flags*/0); 1177 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK); 1178 mtx_lock(&bounce_lock); 1179 } 1180 mtx_unlock(&bounce_lock); 1181 }
Cache object: 0aa316c15805fa8332e30b7e38ee7954
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