sys/platform/pc32/i386/busdma_machdep.c

   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  * $FreeBSD: src/sys/i386/i386/busdma_machdep.c,v 1.16.2.2 2003/01/23 00:55:27 scottl Exp $
  27  * $DragonFly: src/sys/platform/pc32/i386/busdma_machdep.c,v 1.23 2008/06/05 18:06:32 swildner Exp $
  28  */
  29
  30 #include <sys/param.h>
  31 #include <sys/systm.h>
  32 #include <sys/malloc.h>
  33 #include <sys/mbuf.h>
  34 #include <sys/uio.h>
  35 #include <sys/thread2.h>
  36 #include <sys/bus_dma.h>
  37 #include <sys/kernel.h>
  38 #include <sys/sysctl.h>
  39
  40 #include <vm/vm.h>
  41 #include <vm/vm_page.h>
  42
  43 /* XXX needed for to access pmap to convert per-proc virtual to physical */
  44 #include <sys/proc.h>
  45 #include <sys/lock.h>
  46 #include <vm/vm_map.h>
  47
  48 #include <machine/md_var.h>
  49
  50 #define MAX_BPAGES      1024
  51
  52 struct bounce_zone;
  53
  54 struct bus_dma_tag {
  55         bus_dma_tag_t   parent;
  56         bus_size_t      alignment;
  57         bus_size_t      boundary;
  58         bus_addr_t      lowaddr;
  59         bus_addr_t      highaddr;
  60         bus_dma_filter_t *filter;
  61         void            *filterarg;
  62         bus_size_t      maxsize;
  63         u_int           nsegments;
  64         bus_size_t      maxsegsz;
  65         int             flags;
  66         int             ref_count;
  67         int             map_count;
  68         bus_dma_segment_t *segments;
  69         struct bounce_zone *bounce_zone;
  70 };
  71
  72 /*
  73  * bus_dma_tag private flags
  74  */
  75 #define BUS_DMA_COULD_BOUNCE    BUS_DMA_BUS3
  76 #define BUS_DMA_MIN_ALLOC_COMP  BUS_DMA_BUS4
  77
  78 struct bounce_page {
  79         vm_offset_t     vaddr;          /* kva of bounce buffer */
  80         bus_addr_t      busaddr;        /* Physical address */
  81         vm_offset_t     datavaddr;      /* kva of client data */
  82         bus_size_t      datacount;      /* client data count */
  83         STAILQ_ENTRY(bounce_page) links;
  84 };
  85
  86 struct bounce_zone {
  87         STAILQ_ENTRY(bounce_zone) links;
  88         STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
  89         int             total_bpages;
  90         int             free_bpages;
  91         int             reserved_bpages;
  92         int             active_bpages;
  93         int             total_bounced;
  94         int             total_deferred;
  95         int             reserve_failed;
  96         bus_size_t      alignment;
  97         bus_size_t      boundary;
  98         bus_addr_t      lowaddr;
  99         char            zoneid[8];
 100         char            lowaddrid[20];
 101         struct sysctl_ctx_list sysctl_ctx;
 102         struct sysctl_oid *sysctl_tree;
 103 };
 104
 105 static int busdma_zonecount;
 106 static STAILQ_HEAD(, bounce_zone) bounce_zone_list =
 107         STAILQ_HEAD_INITIALIZER(bounce_zone_list);
 108
 109 int busdma_swi_pending;
 110 static int total_bounce_pages;
 111 static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR;
 112
 113 struct bus_dmamap {
 114         struct bp_list  bpages;
 115         int             pagesneeded;
 116         int             pagesreserved;
 117         bus_dma_tag_t   dmat;
 118         void            *buf;           /* unmapped buffer pointer */
 119         bus_size_t      buflen;         /* unmapped buffer length */
 120         bus_dmamap_callback_t *callback;
 121         void            *callback_arg;
 122         STAILQ_ENTRY(bus_dmamap) links;
 123 };
 124
 125 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist =
 126         STAILQ_HEAD_INITIALIZER(bounce_map_waitinglist);
 127
 128 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist =
 129         STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist);
 130
 131 static struct bus_dmamap nobounce_dmamap;
 132
 133 static int              alloc_bounce_zone(bus_dma_tag_t);
 134 static int              alloc_bounce_pages(bus_dma_tag_t, u_int);
 135 static int              reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int);
 136 static bus_addr_t       add_bounce_page(bus_dma_tag_t, bus_dmamap_t,
 137                             vm_offset_t, bus_size_t);
 138 static void             free_bounce_page(bus_dma_tag_t, struct bounce_page *);
 139
 140 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
 141 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages,
 142            0, "Total bounce pages");
 143
 144 static __inline int
 145 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
 146 {
 147         int retval;
 148
 149         retval = 0;
 150         do {
 151                 if (paddr > dmat->lowaddr
 152                  && paddr <= dmat->highaddr
 153                  && (dmat->filter == NULL
 154                   || (*dmat->filter)(dmat->filterarg, paddr) != 0))
 155                         retval = 1;
 156
 157                 dmat = dmat->parent;
 158         } while (retval == 0 && dmat != NULL);
 159         return (retval);
 160 }
 161
 162 /*
 163  * Allocate a device specific dma_tag.
 164  */
 165 int
 166 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
 167                    bus_size_t boundary, bus_addr_t lowaddr,
 168                    bus_addr_t highaddr, bus_dma_filter_t *filter,
 169                    void *filterarg, bus_size_t maxsize, int nsegments,
 170                    bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
 171 {
 172         bus_dma_tag_t newtag;
 173         int error = 0;
 174
 175         if (alignment == 0)
 176                 alignment = 1;
 177
 178         /* Return a NULL tag on failure */
 179         *dmat = NULL;
 180
 181         newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT);
 182
 183         newtag->parent = parent;
 184         newtag->alignment = alignment;
 185         newtag->boundary = boundary;
 186         newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
 187         newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
 188         newtag->filter = filter;
 189         newtag->filterarg = filterarg;
 190         newtag->maxsize = maxsize;
 191         newtag->nsegments = nsegments;
 192         newtag->maxsegsz = maxsegsz;
 193         newtag->flags = flags;
 194         newtag->ref_count = 1; /* Count ourself */
 195         newtag->map_count = 0;
 196         newtag->segments = NULL;
 197         newtag->bounce_zone = NULL;
 198
 199         /* Take into account any restrictions imposed by our parent tag */
 200         if (parent != NULL) {
 201                 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
 202                 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
 203
 204                 if (newtag->boundary == 0) {
 205                         newtag->boundary = parent->boundary;
 206                 } else if (parent->boundary != 0) {
 207                         newtag->boundary = MIN(parent->boundary,
 208                                                newtag->boundary);
 209                 }
 210
 211 #ifdef notyet
 212                 newtag->alignment = MAX(parent->alignment, newtag->alignment);
 213 #endif
 214
 215                 if (newtag->filter == NULL) {
 216                         /*
 217                          * Short circuit looking at our parent directly
 218                          * since we have encapsulated all of its information
 219                          */
 220                         newtag->filter = parent->filter;
 221                         newtag->filterarg = parent->filterarg;
 222                         newtag->parent = parent->parent;
 223                 }
 224                 if (newtag->parent != NULL)
 225                         parent->ref_count++;
 226         }
 227
 228         if (newtag->lowaddr < ptoa(Maxmem))
 229                 newtag->flags |= BUS_DMA_COULD_BOUNCE;
 230
 231         if ((newtag->flags & BUS_DMA_COULD_BOUNCE) &&
 232             (flags & BUS_DMA_ALLOCNOW) != 0) {
 233                 struct bounce_zone *bz;
 234
 235                 /* Must bounce */
 236
 237                 if (lowaddr > bounce_lowaddr) {
 238                         /*
 239                          * Go through the pool and kill any pages
 240                          * that don't reside below lowaddr.
 241                          */
 242                         panic("bus_dma_tag_create: page reallocation "
 243                               "not implemented");
 244                 }
 245
 246                 error = alloc_bounce_zone(newtag);
 247                 if (error)
 248                         goto back;
 249                 bz = newtag->bounce_zone;
 250
 251                 if (ptoa(bz->total_bpages) < maxsize) {
 252                         int pages;
 253
 254                         pages = atop(maxsize) - bz->total_bpages;
 255
 256                         /* Add pages to our bounce pool */
 257                         if (alloc_bounce_pages(newtag, pages) < pages)
 258                                 error = ENOMEM;
 259                 }
 260                 /* Performed initial allocation */
 261                 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
 262         }
 263 back:
 264         if (error)
 265                 kfree(newtag, M_DEVBUF);
 266         else
 267                 *dmat = newtag;
 268         return error;
 269 }
 270
 271 int
 272 bus_dma_tag_destroy(bus_dma_tag_t dmat)
 273 {
 274         if (dmat != NULL) {
 275                 if (dmat->map_count != 0)
 276                         return (EBUSY);
 277
 278                 while (dmat != NULL) {
 279                         bus_dma_tag_t parent;
 280
 281                         parent = dmat->parent;
 282                         dmat->ref_count--;
 283                         if (dmat->ref_count == 0) {
 284                                 if (dmat->segments != NULL)
 285                                         kfree(dmat->segments, M_DEVBUF);
 286                                 kfree(dmat, M_DEVBUF);
 287                                 /*
 288                                  * Last reference count, so
 289                                  * release our reference
 290                                  * count on our parent.
 291                                  */
 292                                 dmat = parent;
 293                         } else
 294                                 dmat = NULL;
 295                 }
 296         }
 297         return (0);
 298 }
 299
 300 /*
 301  * Allocate a handle for mapping from kva/uva/physical
 302  * address space into bus device space.
 303  */
 304 int
 305 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
 306 {
 307         int error;
 308
 309         error = 0;
 310
 311         if (dmat->segments == NULL) {
 312                 KKASSERT(dmat->nsegments && dmat->nsegments < 16384);
 313                 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
 314                                         dmat->nsegments, M_DEVBUF, M_INTWAIT);
 315         }
 316
 317         if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
 318                 struct bounce_zone *bz;
 319                 int maxpages;
 320
 321                 /* Must bounce */
 322
 323                 if (dmat->bounce_zone == NULL) {
 324                         error = alloc_bounce_zone(dmat);
 325                         if (error)
 326                                 return error;
 327                 }
 328                 bz = dmat->bounce_zone;
 329
 330                 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO);
 331
 332                 /* Initialize the new map */
 333                 STAILQ_INIT(&((*mapp)->bpages));
 334                 /*
 335                  * Attempt to add pages to our pool on a per-instance
 336                  * basis up to a sane limit.
 337                  */
 338                 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr));
 339                 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
 340                  || (dmat->map_count > 0
 341                   && bz->total_bpages < maxpages)) {
 342                         int pages;
 343
 344                         if (dmat->lowaddr > bounce_lowaddr) {
 345                                 /*
 346                                  * Go through the pool and kill any pages
 347                                  * that don't reside below lowaddr.
 348                                  */
 349                                 panic("bus_dmamap_create: page reallocation "
 350                                       "not implemented");
 351                         }
 352
 353                         pages = MAX(atop(dmat->maxsize), 1);
 354                         pages = MIN(maxpages - bz->total_bpages, pages);
 355                         pages = MAX(pages, 1);
 356                         if (alloc_bounce_pages(dmat, pages) < pages)
 357                                 error = ENOMEM;
 358
 359                         if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
 360                                 if (!error)
 361                                         dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
 362                         } else {
 363                                 error = 0;
 364                         }
 365                 }
 366         } else {
 367                 *mapp = NULL;
 368         }
 369         if (!error)
 370                 dmat->map_count++;
 371         return error;
 372 }
 373
 374 /*
 375  * Destroy a handle for mapping from kva/uva/physical
 376  * address space into bus device space.
 377  */
 378 int
 379 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
 380 {
 381         if (map != NULL) {
 382                 if (STAILQ_FIRST(&map->bpages) != NULL)
 383                         return (EBUSY);
 384                 kfree(map, M_DEVBUF);
 385         }
 386         dmat->map_count--;
 387         return (0);
 388 }
 389
 390 /*
 391  * Allocate a piece of memory that can be efficiently mapped into
 392  * bus device space based on the constraints lited in the dma tag.
 393  *
 394  * mapp is degenerate.  By definition this allocation should not require
 395  * bounce buffers so do not allocate a dma map.
 396  */
 397 int
 398 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
 399                  bus_dmamap_t *mapp)
 400 {
 401         int mflags;
 402
 403         /* If we succeed, no mapping/bouncing will be required */
 404         *mapp = NULL;
 405
 406         if (dmat->segments == NULL) {
 407                 KKASSERT(dmat->nsegments < 16384);
 408                 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
 409                                         dmat->nsegments, M_DEVBUF, M_INTWAIT);
 410         }
 411
 412         if (flags & BUS_DMA_NOWAIT)
 413                 mflags = M_NOWAIT;
 414         else
 415                 mflags = M_WAITOK;
 416         if (flags & BUS_DMA_ZERO)
 417                 mflags |= M_ZERO;
 418
 419         if ((dmat->maxsize <= PAGE_SIZE) &&
 420             dmat->lowaddr >= ptoa(Maxmem)) {
 421                 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags);
 422                 /*
 423                  * XXX Check whether the allocation crossed a page boundary
 424                  * and retry with power-of-2 alignment in that case.
 425                  */
 426                 if ((((intptr_t)*vaddr) & PAGE_MASK) !=
 427                     (((intptr_t)*vaddr + dmat->maxsize) & PAGE_MASK)) {
 428                         size_t size;
 429
 430                         kfree(*vaddr, M_DEVBUF);
 431                         /* XXX check for overflow? */
 432                         for (size = 1; size <= dmat->maxsize; size <<= 1)
 433                                 ;
 434                         *vaddr = kmalloc(size, M_DEVBUF, mflags);
 435                 }
 436         } else {
 437                 /*
 438                  * XXX Use Contigmalloc until it is merged into this facility
 439                  *     and handles multi-seg allocations.  Nobody is doing
 440                  *     multi-seg allocations yet though.
 441                  */
 442                 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
 443                     0ul, dmat->lowaddr, dmat->alignment, dmat->boundary);
 444         }
 445         if (*vaddr == NULL)
 446                 return (ENOMEM);
 447         return (0);
 448 }
 449
 450 /*
 451  * Free a piece of memory and it's allociated dmamap, that was allocated
 452  * via bus_dmamem_alloc.  Make the same choice for free/contigfree.
 453  */
 454 void
 455 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
 456 {
 457         /*
 458          * dmamem does not need to be bounced, so the map should be
 459          * NULL
 460          */
 461         if (map != NULL)
 462                 panic("bus_dmamem_free: Invalid map freed\n");
 463         if ((dmat->maxsize <= PAGE_SIZE) &&
 464             dmat->lowaddr >= ptoa(Maxmem))
 465                 kfree(vaddr, M_DEVBUF);
 466         else
 467                 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
 468 }
 469
 470 static __inline vm_paddr_t
 471 _bus_dma_extract(pmap_t pmap, vm_offset_t vaddr)
 472 {
 473         if (pmap)
 474                 return pmap_extract(pmap, vaddr);
 475         else
 476                 return pmap_kextract(vaddr);
 477 }
 478
 479 /*
 480  * Utility function to load a linear buffer.  lastaddrp holds state
 481  * between invocations (for multiple-buffer loads).  segp contains
 482  * the segment following the starting one on entrace, and the ending
 483  * segment on exit.  first indicates if this is the first invocation
 484  * of this function.
 485  */
 486 static int
 487 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
 488                         bus_dmamap_t map,
 489                         void *buf, bus_size_t buflen,
 490                         pmap_t pmap,
 491                         int flags,
 492                         vm_paddr_t *lastpaddrp,
 493                         int *segp,
 494                         int first)
 495 {
 496         vm_offset_t vaddr;
 497         vm_paddr_t paddr, nextpaddr;
 498         bus_dma_segment_t *sg;
 499         bus_addr_t bmask;
 500         int seg, error = 0;
 501
 502         if (map == NULL)
 503                 map = &nobounce_dmamap;
 504
 505         /*
 506          * If we are being called during a callback, pagesneeded will
 507          * be non-zero, so we can avoid doing the work twice.
 508          */
 509         if ((dmat->flags & BUS_DMA_COULD_BOUNCE) &&
 510             map != &nobounce_dmamap && map->pagesneeded == 0) {
 511                 vm_offset_t vendaddr;
 512
 513                 /*
 514                  * Count the number of bounce pages
 515                  * needed in order to complete this transfer
 516                  */
 517                 vaddr = (vm_offset_t)buf;
 518                 vendaddr = (vm_offset_t)buf + buflen;
 519
 520                 while (vaddr < vendaddr) {
 521                         paddr = _bus_dma_extract(pmap, vaddr);
 522                         if (run_filter(dmat, paddr) != 0)
 523                                 map->pagesneeded++;
 524                         vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK));
 525                 }
 526         }
 527
 528         /* Reserve Necessary Bounce Pages */
 529         if (map->pagesneeded != 0) {
 530                 crit_enter();
 531                 if (flags & BUS_DMA_NOWAIT) {
 532                         if (reserve_bounce_pages(dmat, map, 0) != 0) {
 533                                 crit_exit();
 534                                 return (ENOMEM);
 535                         }
 536                 } else {
 537                         if (reserve_bounce_pages(dmat, map, 1) != 0) {
 538                                 /* Queue us for resources */
 539                                 map->dmat = dmat;
 540                                 map->buf = buf;
 541                                 map->buflen = buflen;
 542
 543                                 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
 544                                                    map, links);
 545                                 crit_exit();
 546
 547                                 return (EINPROGRESS);
 548                         }
 549                 }
 550                 crit_exit();
 551         }
 552
 553         KKASSERT(*segp >= 1);
 554         seg = *segp;
 555         sg = &dmat->segments[seg - 1];
 556
 557         vaddr = (vm_offset_t)buf;
 558         nextpaddr = *lastpaddrp;
 559         bmask = ~(dmat->boundary - 1);  /* note: will be 0 if boundary is 0 */
 560
 561         /* force at least one segment */
 562         do {
 563                 bus_size_t size;
 564
 565                 /*
 566                  * Per-page main loop
 567                  */
 568                 paddr = _bus_dma_extract(pmap, vaddr);
 569                 size = PAGE_SIZE - (paddr & PAGE_MASK);
 570                 if (size > buflen)
 571                         size = buflen;
 572                 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
 573                         /*
 574                          * note: this paddr has the same in-page offset
 575                          * as vaddr and thus the paddr above, so the
 576                          * size does not have to be recalculated
 577                          */
 578                         paddr = add_bounce_page(dmat, map, vaddr, size);
 579                 }
 580
 581                 /*
 582                  * Fill in the bus_dma_segment
 583                  */
 584                 if (first) {
 585                         sg->ds_addr = paddr;
 586                         sg->ds_len = size;
 587                         first = 0;
 588                 } else if (paddr == nextpaddr) {
 589                         sg->ds_len += size;
 590                 } else {
 591                         sg++;
 592                         seg++;
 593                         if (seg > dmat->nsegments)
 594                                 break;
 595                         sg->ds_addr = paddr;
 596                         sg->ds_len = size;
 597                 }
 598                 nextpaddr = paddr + size;
 599
 600                 /*
 601                  * Handle maxsegsz and boundary issues with a nested loop
 602                  */
 603                 for (;;) {
 604                         bus_size_t tmpsize;
 605
 606                         /*
 607                          * Limit to the boundary and maximum segment size
 608                          */
 609                         if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) {
 610                                 tmpsize = dmat->boundary -
 611                                           (sg->ds_addr & ~bmask);
 612                                 if (tmpsize > dmat->maxsegsz)
 613                                         tmpsize = dmat->maxsegsz;
 614                                 KKASSERT(tmpsize < sg->ds_len);
 615                         } else if (sg->ds_len > dmat->maxsegsz) {
 616                                 tmpsize = dmat->maxsegsz;
 617                         } else {
 618                                 break;
 619                         }
 620
 621                         /*
 622                          * Futz, split the data into a new segment.
 623                          */
 624                         if (seg >= dmat->nsegments)
 625                                 goto fail;
 626                         sg[1].ds_len = sg[0].ds_len - tmpsize;
 627                         sg[1].ds_addr = sg[0].ds_addr + tmpsize;
 628                         sg[0].ds_len = tmpsize;
 629                         sg++;
 630                         seg++;
 631                 }
 632
 633                 /*
 634                  * Adjust for loop
 635                  */
 636                 buflen -= size;
 637                 vaddr += size;
 638         } while (buflen > 0);
 639 fail:
 640         if (buflen != 0) {
 641                 kprintf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",
 642                        (u_long)buflen);
 643                 error = EFBIG;
 644         }
 645
 646         *segp = seg;
 647         *lastpaddrp = nextpaddr;
 648
 649         return error;
 650 }
 651
 652 /*
 653  * Map the buffer buf into bus space using the dmamap map.
 654  */
 655 int
 656 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
 657                 bus_size_t buflen, bus_dmamap_callback_t *callback,
 658                 void *callback_arg, int flags)
 659 {
 660         vm_paddr_t lastaddr = 0;
 661         int error, nsegs = 1;
 662
 663         if (map != NULL) {
 664                 /*
 665                  * XXX
 666                  * Follow old semantics.  Once all of the callers are fixed,
 667                  * we should get rid of these internal flag "adjustment".
 668                  */
 669                 flags &= ~BUS_DMA_NOWAIT;
 670                 flags |= BUS_DMA_WAITOK;
 671
 672                 map->callback = callback;
 673                 map->callback_arg = callback_arg;
 674         }
 675
 676         error = _bus_dmamap_load_buffer(dmat, map, buf, buflen,
 677                         NULL, flags, &lastaddr, &nsegs, 1);
 678         if (error == EINPROGRESS)
 679                 return error;
 680
 681         callback(callback_arg, dmat->segments, nsegs, error);
 682         return 0;
 683 }
 684
 685 /*
 686  * Like _bus_dmamap_load(), but for mbufs.
 687  */
 688 int
 689 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
 690                      struct mbuf *m0,
 691                      bus_dmamap_callback2_t *callback, void *callback_arg,
 692                      int flags)
 693 {
 694         int nsegs, error;
 695
 696         M_ASSERTPKTHDR(m0);
 697
 698         /*
 699          * XXX
 700          * Follow old semantics.  Once all of the callers are fixed,
 701          * we should get rid of these internal flag "adjustment".
 702          */
 703         flags &= ~BUS_DMA_WAITOK;
 704         flags |= BUS_DMA_NOWAIT;
 705
 706         if (m0->m_pkthdr.len <= dmat->maxsize) {
 707                 int first = 1;
 708                 vm_paddr_t lastaddr = 0;
 709                 struct mbuf *m;
 710
 711                 nsegs = 1;
 712                 error = 0;
 713                 for (m = m0; m != NULL && error == 0; m = m->m_next) {
 714                         if (m->m_len == 0)
 715                                 continue;
 716
 717                         error = _bus_dmamap_load_buffer(dmat, map,
 718                                         m->m_data, m->m_len,
 719                                         NULL, flags, &lastaddr,
 720                                         &nsegs, first);
 721                         first = 0;
 722                 }
 723         } else {
 724                 nsegs = 0;
 725                 error = EINVAL;
 726         }
 727
 728         if (error) {
 729                 /* force "no valid mappings" in callback */
 730                 callback(callback_arg, dmat->segments, 0, 0, error);
 731         } else {
 732                 callback(callback_arg, dmat->segments, nsegs,
 733                          m0->m_pkthdr.len, error);
 734         }
 735         return error;
 736 }
 737
 738 /*
 739  * Like _bus_dmamap_load(), but for uios.
 740  */
 741 int
 742 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
 743                     struct uio *uio,
 744                     bus_dmamap_callback2_t *callback, void *callback_arg,
 745                     int flags)
 746 {
 747         vm_paddr_t lastaddr;
 748         int nsegs, error, first, i;
 749         bus_size_t resid;
 750         struct iovec *iov;
 751         pmap_t pmap;
 752
 753         /*
 754          * XXX
 755          * Follow old semantics.  Once all of the callers are fixed,
 756          * we should get rid of these internal flag "adjustment".
 757          */
 758         flags &= ~BUS_DMA_WAITOK;
 759         flags |= BUS_DMA_NOWAIT;
 760
 761         resid = uio->uio_resid;
 762         iov = uio->uio_iov;
 763
 764         if (uio->uio_segflg == UIO_USERSPACE) {
 765                 struct thread *td;
 766
 767                 td = uio->uio_td;
 768                 KASSERT(td != NULL && td->td_proc != NULL,
 769                         ("bus_dmamap_load_uio: USERSPACE but no proc"));
 770                 pmap = vmspace_pmap(td->td_proc->p_vmspace);
 771         } else {
 772                 pmap = NULL;
 773         }
 774
 775         error = 0;
 776         nsegs = 1;
 777         first = 1;
 778         lastaddr = 0;
 779         for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
 780                 /*
 781                  * Now at the first iovec to load.  Load each iovec
 782                  * until we have exhausted the residual count.
 783                  */
 784                 bus_size_t minlen =
 785                         resid < iov[i].iov_len ? resid : iov[i].iov_len;
 786                 caddr_t addr = (caddr_t) iov[i].iov_base;
 787
 788                 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen,
 789                                 pmap, flags, &lastaddr, &nsegs, first);
 790                 first = 0;
 791
 792                 resid -= minlen;
 793         }
 794
 795         if (error) {
 796                 /* force "no valid mappings" in callback */
 797                 callback(callback_arg, dmat->segments, 0, 0, error);
 798         } else {
 799                 callback(callback_arg, dmat->segments, nsegs,
 800                          uio->uio_resid, error);
 801         }
 802         return error;
 803 }
 804
 805 /*
 806  * Release the mapping held by map.
 807  */
 808 void
 809 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
 810 {
 811         struct bounce_page *bpage;
 812
 813         while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
 814                 STAILQ_REMOVE_HEAD(&map->bpages, links);
 815                 free_bounce_page(dmat, bpage);
 816         }
 817 }
 818
 819 void
 820 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
 821 {
 822         struct bounce_page *bpage;
 823
 824         if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
 825                 /*
 826                  * Handle data bouncing.  We might also
 827                  * want to add support for invalidating
 828                  * the caches on broken hardware
 829                  */
 830                 switch (op) {
 831                 case BUS_DMASYNC_PREWRITE:
 832                         while (bpage != NULL) {
 833                                 bcopy((void *)bpage->datavaddr,
 834                                       (void *)bpage->vaddr,
 835                                       bpage->datacount);
 836                                 bpage = STAILQ_NEXT(bpage, links);
 837                         }
 838                         dmat->bounce_zone->total_bounced++;
 839                         break;
 840
 841                 case BUS_DMASYNC_POSTREAD:
 842                         while (bpage != NULL) {
 843                                 bcopy((void *)bpage->vaddr,
 844                                       (void *)bpage->datavaddr,
 845                                       bpage->datacount);
 846                                 bpage = STAILQ_NEXT(bpage, links);
 847                         }
 848                         dmat->bounce_zone->total_bounced++;
 849                         break;
 850
 851                 case BUS_DMASYNC_PREREAD:
 852                 case BUS_DMASYNC_POSTWRITE:
 853                         /* No-ops */
 854                         break;
 855                 }
 856         }
 857 }
 858
 859 static int
 860 alloc_bounce_zone(bus_dma_tag_t dmat)
 861 {
 862         struct bounce_zone *bz;
 863
 864         KASSERT(dmat->bounce_zone == NULL,
 865                 ("bounce zone was already assigned\n"));
 866
 867         /* Check to see if we already have a suitable zone */
 868         STAILQ_FOREACH(bz, &bounce_zone_list, links) {
 869                 if (dmat->alignment <= bz->alignment &&
 870                     dmat->boundary <= bz->boundary &&
 871                     dmat->lowaddr >= bz->lowaddr) {
 872                         dmat->bounce_zone = bz;
 873                         return 0;
 874                 }
 875         }
 876
 877         bz = kmalloc(sizeof(*bz), M_DEVBUF, M_INTWAIT | M_ZERO);
 878
 879         STAILQ_INIT(&bz->bounce_page_list);
 880         bz->free_bpages = 0;
 881         bz->reserved_bpages = 0;
 882         bz->active_bpages = 0;
 883         bz->lowaddr = dmat->lowaddr;
 884         bz->alignment = dmat->alignment;
 885         bz->boundary = dmat->boundary;
 886         ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
 887         busdma_zonecount++;
 888         ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
 889         STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
 890         dmat->bounce_zone = bz;
 891
 892         sysctl_ctx_init(&bz->sysctl_ctx);
 893         bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx,
 894             SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
 895             CTLFLAG_RD, 0, "");
 896         if (bz->sysctl_tree == NULL) {
 897                 sysctl_ctx_free(&bz->sysctl_ctx);
 898                 return 0;       /* XXX error code? */
 899         }
 900
 901         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 902             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 903             "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
 904             "Total bounce pages");
 905         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 906             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 907             "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
 908             "Free bounce pages");
 909         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 910             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 911             "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
 912             "Reserved bounce pages");
 913         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 914             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 915             "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
 916             "Active bounce pages");
 917         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 918             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 919             "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
 920             "Total bounce requests");
 921         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 922             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 923             "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
 924             "Total bounce requests that were deferred");
 925         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 926             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 927             "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0,
 928             "Total bounce page reservations that were failed");
 929         SYSCTL_ADD_STRING(&bz->sysctl_ctx,
 930             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 931             "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
 932         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 933             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 934             "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
 935         SYSCTL_ADD_INT(&bz->sysctl_ctx,
 936             SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
 937             "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
 938
 939         return 0;
 940 }
 941
 942 static int
 943 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
 944 {
 945         struct bounce_zone *bz = dmat->bounce_zone;
 946         int count = 0;
 947
 948         while (numpages > 0) {
 949                 struct bounce_page *bpage;
 950
 951                 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO);
 952
 953                 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
 954                                                          M_NOWAIT, 0ul,
 955                                                          dmat->lowaddr,
 956                                                          PAGE_SIZE,
 957                                                          0);
 958                 if (bpage->vaddr == 0) {
 959                         kfree(bpage, M_DEVBUF);
 960                         break;
 961                 }
 962                 bpage->busaddr = pmap_kextract(bpage->vaddr);
 963
 964                 crit_enter();
 965                 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
 966                 total_bounce_pages++;
 967                 bz->total_bpages++;
 968                 bz->free_bpages++;
 969                 crit_exit();
 970
 971                 count++;
 972                 numpages--;
 973         }
 974         return count;
 975 }
 976
 977 static int
 978 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
 979 {
 980         struct bounce_zone *bz = dmat->bounce_zone;
 981         int pages;
 982
 983         pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
 984         if (!commit && map->pagesneeded > (map->pagesreserved + pages)) {
 985                 bz->reserve_failed++;
 986                 return (map->pagesneeded - (map->pagesreserved + pages));
 987         }
 988         bz->free_bpages -= pages;
 989         bz->reserved_bpages += pages;
 990         map->pagesreserved += pages;
 991         pages = map->pagesneeded - map->pagesreserved;
 992
 993         return pages;
 994 }
 995
 996 static bus_addr_t
 997 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
 998                 bus_size_t size)
 999 {
1000         struct bounce_zone *bz = dmat->bounce_zone;
1001         struct bounce_page *bpage;
1002
1003         if (map->pagesneeded == 0)
1004                 panic("add_bounce_page: map doesn't need any pages");
1005         map->pagesneeded--;
1006
1007         if (map->pagesreserved == 0)
1008                 panic("add_bounce_page: map doesn't need any pages");
1009         map->pagesreserved--;
1010
1011         crit_enter();
1012         bpage = STAILQ_FIRST(&bz->bounce_page_list);
1013         if (bpage == NULL)
1014                 panic("add_bounce_page: free page list is empty");
1015
1016         STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1017         bz->reserved_bpages--;
1018         bz->active_bpages++;
1019         crit_exit();
1020
1021         bpage->datavaddr = vaddr;
1022         bpage->datacount = size;
1023         STAILQ_INSERT_TAIL(&map->bpages, bpage, links);
1024         return bpage->busaddr;
1025 }
1026
1027 static void
1028 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1029 {
1030         struct bounce_zone *bz = dmat->bounce_zone;
1031         struct bus_dmamap *map;
1032
1033         bpage->datavaddr = 0;
1034         bpage->datacount = 0;
1035
1036         crit_enter();
1037         STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1038         bz->free_bpages++;
1039         bz->active_bpages--;
1040         if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1041                 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1042                         STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1043                         STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1044                                            map, links);
1045                         busdma_swi_pending = 1;
1046                         bz->total_deferred++;
1047                         setsoftvm();
1048                 }
1049         }
1050         crit_exit();
1051 }
1052
1053 void
1054 busdma_swi(void)
1055 {
1056         struct bus_dmamap *map;
1057
1058         crit_enter();
1059         while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1060                 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1061                 crit_exit();
1062                 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1063                                 map->callback, map->callback_arg, /*flags*/0);
1064                 crit_enter();
1065         }
1066         crit_exit();
1067 }