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/6.2/sys/amd64/amd64/busdma_machdep.c 163580 2006-10-21 16:27:50Z hrs $");
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
33 #include <sys/bus.h>
34 #include <sys/interrupt.h>
35 #include <sys/kernel.h>
36 #include <sys/ktr.h>
37 #include <sys/lock.h>
38 #include <sys/proc.h>
39 #include <sys/mutex.h>
40 #include <sys/mbuf.h>
41 #include <sys/uio.h>
42 #include <sys/sysctl.h>
43
44 #include <vm/vm.h>
45 #include <vm/vm_page.h>
46 #include <vm/vm_map.h>
47
48 #include <machine/atomic.h>
49 #include <machine/bus.h>
50 #include <machine/md_var.h>
51
52 #define MAX_BPAGES 8192
53
54 struct bounce_zone;
55
56 struct bus_dma_tag {
57 bus_dma_tag_t parent;
58 bus_size_t alignment;
59 bus_size_t boundary;
60 bus_addr_t lowaddr;
61 bus_addr_t highaddr;
62 bus_dma_filter_t *filter;
63 void *filterarg;
64 bus_size_t maxsize;
65 u_int nsegments;
66 bus_size_t maxsegsz;
67 int flags;
68 int ref_count;
69 int map_count;
70 bus_dma_lock_t *lockfunc;
71 void *lockfuncarg;
72 bus_dma_segment_t *segments;
73 struct bounce_zone *bounce_zone;
74 };
75
76 struct bounce_page {
77 vm_offset_t vaddr; /* kva of bounce buffer */
78 bus_addr_t busaddr; /* Physical address */
79 vm_offset_t datavaddr; /* kva of client data */
80 bus_size_t datacount; /* client data count */
81 STAILQ_ENTRY(bounce_page) links;
82 };
83
84 int busdma_swi_pending;
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 bus_size_t alignment;
96 bus_size_t boundary;
97 bus_addr_t lowaddr;
98 char zoneid[8];
99 char lowaddrid[20];
100 struct sysctl_ctx_list sysctl_tree;
101 struct sysctl_oid *sysctl_tree_top;
102 };
103
104 static struct mtx bounce_lock;
105 static int total_bpages;
106 static int busdma_zonecount;
107 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
108
109 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
110 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
111 "Total bounce pages");
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 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
127 static struct bus_dmamap nobounce_dmamap;
128
129 static void init_bounce_pages(void *dummy);
130 static int alloc_bounce_zone(bus_dma_tag_t dmat);
131 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
132 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
133 int commit);
134 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
135 vm_offset_t vaddr, bus_size_t size);
136 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
137 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
138
139 /*
140 * Return true if a match is made.
141 *
142 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
143 *
144 * If paddr is within the bounds of the dma tag then call the filter callback
145 * to check for a match, if there is no filter callback then assume a match.
146 */
147 static __inline int
148 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
149 {
150 int retval;
151
152 retval = 0;
153
154 do {
155 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
156 || ((paddr & (dmat->alignment - 1)) != 0))
157 && (dmat->filter == NULL
158 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
159 retval = 1;
160
161 dmat = dmat->parent;
162 } while (retval == 0 && dmat != NULL);
163 return (retval);
164 }
165
166 /*
167 * Convenience function for manipulating driver locks from busdma (during
168 * busdma_swi, for example). Drivers that don't provide their own locks
169 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
170 * non-mutex locking scheme don't have to use this at all.
171 */
172 void
173 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
174 {
175 struct mtx *dmtx;
176
177 dmtx = (struct mtx *)arg;
178 switch (op) {
179 case BUS_DMA_LOCK:
180 mtx_lock(dmtx);
181 break;
182 case BUS_DMA_UNLOCK:
183 mtx_unlock(dmtx);
184 break;
185 default:
186 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
187 }
188 }
189
190 /*
191 * dflt_lock should never get called. It gets put into the dma tag when
192 * lockfunc == NULL, which is only valid if the maps that are associated
193 * with the tag are meant to never be defered.
194 * XXX Should have a way to identify which driver is responsible here.
195 */
196 static void
197 dflt_lock(void *arg, bus_dma_lock_op_t op)
198 {
199 panic("driver error: busdma dflt_lock called");
200 }
201
202 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
203 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
204 /*
205 * Allocate a device specific dma_tag.
206 */
207 int
208 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
209 bus_size_t boundary, bus_addr_t lowaddr,
210 bus_addr_t highaddr, bus_dma_filter_t *filter,
211 void *filterarg, bus_size_t maxsize, int nsegments,
212 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
213 void *lockfuncarg, bus_dma_tag_t *dmat)
214 {
215 bus_dma_tag_t newtag;
216 int error = 0;
217
218 /* Basic sanity checking */
219 if (boundary != 0 && boundary < maxsegsz)
220 maxsegsz = boundary;
221
222 /* Return a NULL tag on failure */
223 *dmat = NULL;
224
225 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
226 M_ZERO | M_NOWAIT);
227 if (newtag == NULL) {
228 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
229 __func__, newtag, 0, error);
230 return (ENOMEM);
231 }
232
233 newtag->parent = parent;
234 newtag->alignment = alignment;
235 newtag->boundary = boundary;
236 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
237 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) +
238 (PAGE_SIZE - 1);
239 newtag->filter = filter;
240 newtag->filterarg = filterarg;
241 newtag->maxsize = maxsize;
242 newtag->nsegments = nsegments;
243 newtag->maxsegsz = maxsegsz;
244 newtag->flags = flags;
245 newtag->ref_count = 1; /* Count ourself */
246 newtag->map_count = 0;
247 if (lockfunc != NULL) {
248 newtag->lockfunc = lockfunc;
249 newtag->lockfuncarg = lockfuncarg;
250 } else {
251 newtag->lockfunc = dflt_lock;
252 newtag->lockfuncarg = NULL;
253 }
254 newtag->segments = NULL;
255
256 /* Take into account any restrictions imposed by our parent tag */
257 if (parent != NULL) {
258 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
259 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
260 if (newtag->boundary == 0)
261 newtag->boundary = parent->boundary;
262 else if (parent->boundary != 0)
263 newtag->boundary = MIN(parent->boundary,
264 newtag->boundary);
265 if (newtag->filter == NULL) {
266 /*
267 * Short circuit looking at our parent directly
268 * since we have encapsulated all of its information
269 */
270 newtag->filter = parent->filter;
271 newtag->filterarg = parent->filterarg;
272 newtag->parent = parent->parent;
273 }
274 if (newtag->parent != NULL)
275 atomic_add_int(&parent->ref_count, 1);
276 }
277
278 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
279 || newtag->alignment > 1)
280 newtag->flags |= BUS_DMA_COULD_BOUNCE;
281
282 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
283 (flags & BUS_DMA_ALLOCNOW) != 0) {
284 struct bounce_zone *bz;
285
286 /* Must bounce */
287
288 if ((error = alloc_bounce_zone(newtag)) != 0) {
289 free(newtag, M_DEVBUF);
290 return (error);
291 }
292 bz = newtag->bounce_zone;
293
294 if (ptoa(bz->total_bpages) < maxsize) {
295 int pages;
296
297 pages = atop(maxsize) - bz->total_bpages;
298
299 /* Add pages to our bounce pool */
300 if (alloc_bounce_pages(newtag, pages) < pages)
301 error = ENOMEM;
302 }
303 /* Performed initial allocation */
304 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
305 }
306
307 if (error != 0) {
308 free(newtag, M_DEVBUF);
309 } else {
310 *dmat = newtag;
311 }
312 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
313 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
314 return (error);
315 }
316
317 int
318 bus_dma_tag_destroy(bus_dma_tag_t dmat)
319 {
320 bus_dma_tag_t dmat_copy;
321 int error;
322
323 error = 0;
324 dmat_copy = dmat;
325
326 if (dmat != NULL) {
327
328 if (dmat->map_count != 0) {
329 error = EBUSY;
330 goto out;
331 }
332
333 while (dmat != NULL) {
334 bus_dma_tag_t parent;
335
336 parent = dmat->parent;
337 atomic_subtract_int(&dmat->ref_count, 1);
338 if (dmat->ref_count == 0) {
339 if (dmat->segments != NULL)
340 free(dmat->segments, M_DEVBUF);
341 free(dmat, M_DEVBUF);
342 /*
343 * Last reference count, so
344 * release our reference
345 * count on our parent.
346 */
347 dmat = parent;
348 } else
349 dmat = NULL;
350 }
351 }
352 out:
353 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
354 return (error);
355 }
356
357 /*
358 * Allocate a handle for mapping from kva/uva/physical
359 * address space into bus device space.
360 */
361 int
362 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
363 {
364 int error;
365
366 error = 0;
367
368 if (dmat->segments == NULL) {
369 dmat->segments = (bus_dma_segment_t *)malloc(
370 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
371 M_NOWAIT);
372 if (dmat->segments == NULL) {
373 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
374 __func__, dmat, ENOMEM);
375 return (ENOMEM);
376 }
377 }
378
379 /*
380 * Bouncing might be required if the driver asks for an active
381 * exclusion region, a data alignment that is stricter than 1, and/or
382 * an active address boundary.
383 */
384 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
385
386 /* Must bounce */
387 struct bounce_zone *bz;
388 int maxpages;
389
390 if (dmat->bounce_zone == NULL) {
391 if ((error = alloc_bounce_zone(dmat)) != 0)
392 return (error);
393 }
394 bz = dmat->bounce_zone;
395
396 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
397 M_NOWAIT | M_ZERO);
398 if (*mapp == NULL) {
399 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
400 __func__, dmat, ENOMEM);
401 return (ENOMEM);
402 }
403
404 /* Initialize the new map */
405 STAILQ_INIT(&((*mapp)->bpages));
406
407 /*
408 * Attempt to add pages to our pool on a per-instance
409 * basis up to a sane limit.
410 */
411 if (dmat->alignment > 1)
412 maxpages = MAX_BPAGES;
413 else
414 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
415 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
416 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
417 int pages;
418
419 pages = MAX(atop(dmat->maxsize), 1);
420 pages = MIN(maxpages - bz->total_bpages, pages);
421 pages = MAX(pages, 1);
422 if (alloc_bounce_pages(dmat, pages) < pages)
423 error = ENOMEM;
424
425 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
426 if (error == 0)
427 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
428 } else {
429 error = 0;
430 }
431 }
432 } else {
433 *mapp = NULL;
434 }
435 if (error == 0)
436 dmat->map_count++;
437 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
438 __func__, dmat, dmat->flags, error);
439 return (error);
440 }
441
442 /*
443 * Destroy a handle for mapping from kva/uva/physical
444 * address space into bus device space.
445 */
446 int
447 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
448 {
449 if (map != NULL && map != &nobounce_dmamap) {
450 if (STAILQ_FIRST(&map->bpages) != NULL) {
451 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
452 __func__, dmat, EBUSY);
453 return (EBUSY);
454 }
455 free(map, M_DEVBUF);
456 }
457 dmat->map_count--;
458 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
459 return (0);
460 }
461
462
463 /*
464 * Allocate a piece of memory that can be efficiently mapped into
465 * bus device space based on the constraints lited in the dma tag.
466 * A dmamap to for use with dmamap_load is also allocated.
467 */
468 int
469 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
470 bus_dmamap_t *mapp)
471 {
472 int mflags;
473
474 if (flags & BUS_DMA_NOWAIT)
475 mflags = M_NOWAIT;
476 else
477 mflags = M_WAITOK;
478 if (flags & BUS_DMA_ZERO)
479 mflags |= M_ZERO;
480
481 /* If we succeed, no mapping/bouncing will be required */
482 *mapp = NULL;
483
484 if (dmat->segments == NULL) {
485 dmat->segments = (bus_dma_segment_t *)malloc(
486 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
487 M_NOWAIT);
488 if (dmat->segments == NULL) {
489 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
490 __func__, dmat, dmat->flags, ENOMEM);
491 return (ENOMEM);
492 }
493 }
494
495 /*
496 * XXX:
497 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
498 * alignment guarantees of malloc need to be nailed down, and the
499 * code below should be rewritten to take that into account.
500 *
501 * In the meantime, we'll warn the user if malloc gets it wrong.
502 */
503 if ((dmat->maxsize <= PAGE_SIZE) &&
504 (dmat->alignment < dmat->maxsize) &&
505 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
506 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
507 } else {
508 /*
509 * XXX Use Contigmalloc until it is merged into this facility
510 * and handles multi-seg allocations. Nobody is doing
511 * multi-seg allocations yet though.
512 * XXX Certain AGP hardware does.
513 */
514 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
515 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
516 dmat->boundary);
517 }
518 if (*vaddr == NULL) {
519 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
520 __func__, dmat, dmat->flags, ENOMEM);
521 return (ENOMEM);
522 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
523 printf("bus_dmamem_alloc failed to align memory properly.\n");
524 }
525 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
526 __func__, dmat, dmat->flags, ENOMEM);
527 return (0);
528 }
529
530 /*
531 * Free a piece of memory and it's allociated dmamap, that was allocated
532 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
533 */
534 void
535 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
536 {
537 /*
538 * dmamem does not need to be bounced, so the map should be
539 * NULL
540 */
541 if (map != NULL)
542 panic("bus_dmamem_free: Invalid map freed\n");
543 if ((dmat->maxsize <= PAGE_SIZE) &&
544 (dmat->alignment < dmat->maxsize) &&
545 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
546 free(vaddr, M_DEVBUF);
547 else {
548 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
549 }
550 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
551 }
552
553 /*
554 * Utility function to load a linear buffer. lastaddrp holds state
555 * between invocations (for multiple-buffer loads). segp contains
556 * the starting segment on entrace, and the ending segment on exit.
557 * first indicates if this is the first invocation of this function.
558 */
559 static __inline int
560 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
561 bus_dmamap_t map,
562 void *buf, bus_size_t buflen,
563 pmap_t pmap,
564 int flags,
565 bus_addr_t *lastaddrp,
566 bus_dma_segment_t *segs,
567 int *segp,
568 int first)
569 {
570 bus_size_t sgsize;
571 bus_addr_t curaddr, lastaddr, baddr, bmask;
572 vm_offset_t vaddr;
573 bus_addr_t paddr;
574 int needbounce = 0;
575 int seg;
576
577 if (map == NULL)
578 map = &nobounce_dmamap;
579
580 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
581 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
582 vm_offset_t vendaddr;
583
584 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
585 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
586 dmat->boundary, dmat->alignment);
587 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
588 map, &nobounce_dmamap, map->pagesneeded);
589 /*
590 * Count the number of bounce pages
591 * needed in order to complete this transfer
592 */
593 vaddr = trunc_page((vm_offset_t)buf);
594 vendaddr = (vm_offset_t)buf + buflen;
595
596 while (vaddr < vendaddr) {
597 paddr = pmap_kextract(vaddr);
598 if (run_filter(dmat, paddr) != 0) {
599 needbounce = 1;
600 map->pagesneeded++;
601 }
602 vaddr += PAGE_SIZE;
603 }
604 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
605 }
606
607 /* Reserve Necessary Bounce Pages */
608 if (map->pagesneeded != 0) {
609 mtx_lock(&bounce_lock);
610 if (flags & BUS_DMA_NOWAIT) {
611 if (reserve_bounce_pages(dmat, map, 0) != 0) {
612 mtx_unlock(&bounce_lock);
613 return (ENOMEM);
614 }
615 } else {
616 if (reserve_bounce_pages(dmat, map, 1) != 0) {
617 /* Queue us for resources */
618 map->dmat = dmat;
619 map->buf = buf;
620 map->buflen = buflen;
621 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
622 map, links);
623 mtx_unlock(&bounce_lock);
624 return (EINPROGRESS);
625 }
626 }
627 mtx_unlock(&bounce_lock);
628 }
629
630 vaddr = (vm_offset_t)buf;
631 lastaddr = *lastaddrp;
632 bmask = ~(dmat->boundary - 1);
633
634 for (seg = *segp; buflen > 0 ; ) {
635 /*
636 * Get the physical address for this segment.
637 */
638 if (pmap)
639 curaddr = pmap_extract(pmap, vaddr);
640 else
641 curaddr = pmap_kextract(vaddr);
642
643 /*
644 * Compute the segment size, and adjust counts.
645 */
646 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
647 if (buflen < sgsize)
648 sgsize = buflen;
649
650 /*
651 * Make sure we don't cross any boundaries.
652 */
653 if (dmat->boundary > 0) {
654 baddr = (curaddr + dmat->boundary) & bmask;
655 if (sgsize > (baddr - curaddr))
656 sgsize = (baddr - curaddr);
657 }
658
659 if (map->pagesneeded != 0 && run_filter(dmat, curaddr))
660 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
661
662 /*
663 * Insert chunk into a segment, coalescing with
664 * previous segment if possible.
665 */
666 if (first) {
667 segs[seg].ds_addr = curaddr;
668 segs[seg].ds_len = sgsize;
669 first = 0;
670 } else {
671 if (needbounce == 0 && curaddr == lastaddr &&
672 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
673 (dmat->boundary == 0 ||
674 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
675 segs[seg].ds_len += sgsize;
676 else {
677 if (++seg >= dmat->nsegments)
678 break;
679 segs[seg].ds_addr = curaddr;
680 segs[seg].ds_len = sgsize;
681 }
682 }
683
684 lastaddr = curaddr + sgsize;
685 vaddr += sgsize;
686 buflen -= sgsize;
687 }
688
689 *segp = seg;
690 *lastaddrp = lastaddr;
691
692 /*
693 * Did we fit?
694 */
695 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
696 }
697
698 /*
699 * Map the buffer buf into bus space using the dmamap map.
700 */
701 int
702 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
703 bus_size_t buflen, bus_dmamap_callback_t *callback,
704 void *callback_arg, int flags)
705 {
706 bus_addr_t lastaddr = 0;
707 int error, nsegs = 0;
708
709 if (map != NULL) {
710 flags |= BUS_DMA_WAITOK;
711 map->callback = callback;
712 map->callback_arg = callback_arg;
713 }
714
715 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
716 &lastaddr, dmat->segments, &nsegs, 1);
717
718 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
719 __func__, dmat, dmat->flags, error, nsegs + 1);
720
721 if (error == EINPROGRESS) {
722 return (error);
723 }
724
725 if (error)
726 (*callback)(callback_arg, dmat->segments, 0, error);
727 else
728 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
729
730 /*
731 * Return ENOMEM to the caller so that it can pass it up the stack.
732 * This error only happens when NOWAIT is set, so deferal is disabled.
733 */
734 if (error == ENOMEM)
735 return (error);
736
737 return (0);
738 }
739
740
741 /*
742 * Like _bus_dmamap_load(), but for mbufs.
743 */
744 int
745 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
746 struct mbuf *m0,
747 bus_dmamap_callback2_t *callback, void *callback_arg,
748 int flags)
749 {
750 int nsegs, error;
751
752 M_ASSERTPKTHDR(m0);
753
754 flags |= BUS_DMA_NOWAIT;
755 nsegs = 0;
756 error = 0;
757 if (m0->m_pkthdr.len <= dmat->maxsize) {
758 int first = 1;
759 bus_addr_t lastaddr = 0;
760 struct mbuf *m;
761
762 for (m = m0; m != NULL && error == 0; m = m->m_next) {
763 if (m->m_len > 0) {
764 error = _bus_dmamap_load_buffer(dmat, map,
765 m->m_data, m->m_len,
766 NULL, flags, &lastaddr,
767 dmat->segments, &nsegs, first);
768 first = 0;
769 }
770 }
771 } else {
772 error = EINVAL;
773 }
774
775 if (error) {
776 /* force "no valid mappings" in callback */
777 (*callback)(callback_arg, dmat->segments, 0, 0, error);
778 } else {
779 (*callback)(callback_arg, dmat->segments,
780 nsegs+1, m0->m_pkthdr.len, error);
781 }
782 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
783 __func__, dmat, dmat->flags, error, nsegs + 1);
784 return (error);
785 }
786
787 int
788 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
789 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
790 int flags)
791 {
792 int error;
793
794 M_ASSERTPKTHDR(m0);
795
796 flags |= BUS_DMA_NOWAIT;
797 *nsegs = 0;
798 error = 0;
799 if (m0->m_pkthdr.len <= dmat->maxsize) {
800 int first = 1;
801 bus_addr_t lastaddr = 0;
802 struct mbuf *m;
803
804 for (m = m0; m != NULL && error == 0; m = m->m_next) {
805 if (m->m_len > 0) {
806 error = _bus_dmamap_load_buffer(dmat, map,
807 m->m_data, m->m_len,
808 NULL, flags, &lastaddr,
809 segs, nsegs, first);
810 first = 0;
811 }
812 }
813 } else {
814 error = EINVAL;
815 }
816
817 /* XXX FIXME: Having to increment nsegs is really annoying */
818 ++*nsegs;
819 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
820 __func__, dmat, dmat->flags, error, *nsegs);
821 return (error);
822 }
823
824 /*
825 * Like _bus_dmamap_load(), but for uios.
826 */
827 int
828 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
829 struct uio *uio,
830 bus_dmamap_callback2_t *callback, void *callback_arg,
831 int flags)
832 {
833 bus_addr_t lastaddr;
834 int nsegs, error, first, i;
835 bus_size_t resid;
836 struct iovec *iov;
837 pmap_t pmap;
838
839 flags |= BUS_DMA_NOWAIT;
840 resid = uio->uio_resid;
841 iov = uio->uio_iov;
842
843 if (uio->uio_segflg == UIO_USERSPACE) {
844 KASSERT(uio->uio_td != NULL,
845 ("bus_dmamap_load_uio: USERSPACE but no proc"));
846 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
847 } else
848 pmap = NULL;
849
850 nsegs = 0;
851 error = 0;
852 first = 1;
853 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
854 /*
855 * Now at the first iovec to load. Load each iovec
856 * until we have exhausted the residual count.
857 */
858 bus_size_t minlen =
859 resid < iov[i].iov_len ? resid : iov[i].iov_len;
860 caddr_t addr = (caddr_t) iov[i].iov_base;
861
862 if (minlen > 0) {
863 error = _bus_dmamap_load_buffer(dmat, map,
864 addr, minlen, pmap, flags, &lastaddr,
865 dmat->segments, &nsegs, first);
866 first = 0;
867
868 resid -= minlen;
869 }
870 }
871
872 if (error) {
873 /* force "no valid mappings" in callback */
874 (*callback)(callback_arg, dmat->segments, 0, 0, error);
875 } else {
876 (*callback)(callback_arg, dmat->segments,
877 nsegs+1, uio->uio_resid, error);
878 }
879 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
880 __func__, dmat, dmat->flags, error, nsegs + 1);
881 return (error);
882 }
883
884 /*
885 * Release the mapping held by map.
886 */
887 void
888 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
889 {
890 struct bounce_page *bpage;
891
892 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
893 STAILQ_REMOVE_HEAD(&map->bpages, links);
894 free_bounce_page(dmat, bpage);
895 }
896 }
897
898 void
899 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
900 {
901 struct bounce_page *bpage;
902
903 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
904 /*
905 * Handle data bouncing. We might also
906 * want to add support for invalidating
907 * the caches on broken hardware
908 */
909 dmat->bounce_zone->total_bounced++;
910 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
911 "performing bounce", __func__, op, dmat, dmat->flags);
912
913 if (op & BUS_DMASYNC_PREWRITE) {
914 while (bpage != NULL) {
915 bcopy((void *)bpage->datavaddr,
916 (void *)bpage->vaddr,
917 bpage->datacount);
918 bpage = STAILQ_NEXT(bpage, links);
919 }
920 }
921
922 if (op & BUS_DMASYNC_POSTREAD) {
923 while (bpage != NULL) {
924 bcopy((void *)bpage->vaddr,
925 (void *)bpage->datavaddr,
926 bpage->datacount);
927 bpage = STAILQ_NEXT(bpage, links);
928 }
929 }
930 }
931 }
932
933 static void
934 init_bounce_pages(void *dummy __unused)
935 {
936
937 total_bpages = 0;
938 STAILQ_INIT(&bounce_zone_list);
939 STAILQ_INIT(&bounce_map_waitinglist);
940 STAILQ_INIT(&bounce_map_callbacklist);
941 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
942 }
943 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
944
945 static struct sysctl_ctx_list *
946 busdma_sysctl_tree(struct bounce_zone *bz)
947 {
948 return (&bz->sysctl_tree);
949 }
950
951 static struct sysctl_oid *
952 busdma_sysctl_tree_top(struct bounce_zone *bz)
953 {
954 return (bz->sysctl_tree_top);
955 }
956
957 static int
958 alloc_bounce_zone(bus_dma_tag_t dmat)
959 {
960 struct bounce_zone *bz;
961
962 /* Check to see if we already have a suitable zone */
963 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
964 if ((dmat->alignment <= bz->alignment)
965 && (dmat->boundary <= bz->boundary)
966 && (dmat->lowaddr >= bz->lowaddr)) {
967 dmat->bounce_zone = bz;
968 return (0);
969 }
970 }
971
972 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
973 M_NOWAIT | M_ZERO)) == NULL)
974 return (ENOMEM);
975
976 STAILQ_INIT(&bz->bounce_page_list);
977 bz->free_bpages = 0;
978 bz->reserved_bpages = 0;
979 bz->active_bpages = 0;
980 bz->lowaddr = dmat->lowaddr;
981 bz->alignment = dmat->alignment;
982 bz->boundary = dmat->boundary;
983 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
984 busdma_zonecount++;
985 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
986 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
987 dmat->bounce_zone = bz;
988
989 sysctl_ctx_init(&bz->sysctl_tree);
990 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
991 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
992 CTLFLAG_RD, 0, "");
993 if (bz->sysctl_tree_top == NULL) {
994 sysctl_ctx_free(&bz->sysctl_tree);
995 return (0); /* XXX error code? */
996 }
997
998 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
999 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1000 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1001 "Total bounce pages");
1002 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1003 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1004 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1005 "Free bounce pages");
1006 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1007 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1008 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1009 "Reserved bounce pages");
1010 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1011 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1012 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1013 "Active bounce pages");
1014 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1016 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1017 "Total bounce requests");
1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1020 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1021 "Total bounce requests that were deferred");
1022 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1023 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1024 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1025 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1026 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1027 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1028 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1029 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1030 "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
1031
1032 return (0);
1033 }
1034
1035 static int
1036 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1037 {
1038 struct bounce_zone *bz;
1039 int count;
1040
1041 bz = dmat->bounce_zone;
1042 count = 0;
1043 while (numpages > 0) {
1044 struct bounce_page *bpage;
1045
1046 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1047 M_NOWAIT | M_ZERO);
1048
1049 if (bpage == NULL)
1050 break;
1051 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1052 M_NOWAIT, 0ul,
1053 bz->lowaddr,
1054 PAGE_SIZE,
1055 bz->boundary);
1056 if (bpage->vaddr == 0) {
1057 free(bpage, M_DEVBUF);
1058 break;
1059 }
1060 bpage->busaddr = pmap_kextract(bpage->vaddr);
1061 mtx_lock(&bounce_lock);
1062 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1063 total_bpages++;
1064 bz->total_bpages++;
1065 bz->free_bpages++;
1066 mtx_unlock(&bounce_lock);
1067 count++;
1068 numpages--;
1069 }
1070 return (count);
1071 }
1072
1073 static int
1074 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1075 {
1076 struct bounce_zone *bz;
1077 int pages;
1078
1079 mtx_assert(&bounce_lock, MA_OWNED);
1080 bz = dmat->bounce_zone;
1081 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1082 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1083 return (map->pagesneeded - (map->pagesreserved + pages));
1084 bz->free_bpages -= pages;
1085 bz->reserved_bpages += pages;
1086 map->pagesreserved += pages;
1087 pages = map->pagesneeded - map->pagesreserved;
1088
1089 return (pages);
1090 }
1091
1092 static bus_addr_t
1093 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1094 bus_size_t size)
1095 {
1096 struct bounce_zone *bz;
1097 struct bounce_page *bpage;
1098
1099 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1100 KASSERT(map != NULL && map != &nobounce_dmamap,
1101 ("add_bounce_page: bad map %p", map));
1102
1103 bz = dmat->bounce_zone;
1104 if (map->pagesneeded == 0)
1105 panic("add_bounce_page: map doesn't need any pages");
1106 map->pagesneeded--;
1107
1108 if (map->pagesreserved == 0)
1109 panic("add_bounce_page: map doesn't need any pages");
1110 map->pagesreserved--;
1111
1112 mtx_lock(&bounce_lock);
1113 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1114 if (bpage == NULL)
1115 panic("add_bounce_page: free page list is empty");
1116
1117 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1118 bz->reserved_bpages--;
1119 bz->active_bpages++;
1120 mtx_unlock(&bounce_lock);
1121
1122 bpage->datavaddr = vaddr;
1123 bpage->datacount = size;
1124 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1125 return (bpage->busaddr);
1126 }
1127
1128 static void
1129 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1130 {
1131 struct bus_dmamap *map;
1132 struct bounce_zone *bz;
1133
1134 bz = dmat->bounce_zone;
1135 bpage->datavaddr = 0;
1136 bpage->datacount = 0;
1137
1138 mtx_lock(&bounce_lock);
1139 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1140 bz->free_bpages++;
1141 bz->active_bpages--;
1142 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1143 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1144 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1145 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1146 map, links);
1147 busdma_swi_pending = 1;
1148 bz->total_deferred++;
1149 swi_sched(vm_ih, 0);
1150 }
1151 }
1152 mtx_unlock(&bounce_lock);
1153 }
1154
1155 void
1156 busdma_swi(void)
1157 {
1158 bus_dma_tag_t dmat;
1159 struct bus_dmamap *map;
1160
1161 mtx_lock(&bounce_lock);
1162 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1163 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1164 mtx_unlock(&bounce_lock);
1165 dmat = map->dmat;
1166 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1167 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1168 map->callback, map->callback_arg, /*flags*/0);
1169 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1170 mtx_lock(&bounce_lock);
1171 }
1172 mtx_unlock(&bounce_lock);
1173 }
Cache object: c16ccd247184b80b0970115ce4fb106c
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