1 /*-
2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions, and the following disclaimer,
10 * without modification, immediately at the beginning of the file.
11 * 2. The name of the author may not be used to endorse or promote products
12 * derived from this software without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
18 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: releng/8.1/sys/amd64/amd64/busdma_machdep.c 206610 2010-04-14 17:01:29Z gibbs $");
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
33 #include <sys/bus.h>
34 #include <sys/interrupt.h>
35 #include <sys/kernel.h>
36 #include <sys/ktr.h>
37 #include <sys/lock.h>
38 #include <sys/proc.h>
39 #include <sys/mutex.h>
40 #include <sys/mbuf.h>
41 #include <sys/uio.h>
42 #include <sys/sysctl.h>
43
44 #include <vm/vm.h>
45 #include <vm/vm_page.h>
46 #include <vm/vm_map.h>
47
48 #include <machine/atomic.h>
49 #include <machine/bus.h>
50 #include <machine/md_var.h>
51 #include <machine/specialreg.h>
52
53 #define MAX_BPAGES 8192
54
55 struct bounce_zone;
56
57 struct bus_dma_tag {
58 bus_dma_tag_t parent;
59 bus_size_t alignment;
60 bus_size_t boundary;
61 bus_addr_t lowaddr;
62 bus_addr_t highaddr;
63 bus_dma_filter_t *filter;
64 void *filterarg;
65 bus_size_t maxsize;
66 u_int nsegments;
67 bus_size_t maxsegsz;
68 int flags;
69 int ref_count;
70 int map_count;
71 bus_dma_lock_t *lockfunc;
72 void *lockfuncarg;
73 bus_dma_segment_t *segments;
74 struct bounce_zone *bounce_zone;
75 };
76
77 struct bounce_page {
78 vm_offset_t vaddr; /* kva of bounce buffer */
79 bus_addr_t busaddr; /* Physical address */
80 vm_offset_t datavaddr; /* kva of client data */
81 bus_size_t datacount; /* client data count */
82 STAILQ_ENTRY(bounce_page) links;
83 };
84
85 int busdma_swi_pending;
86
87 struct bounce_zone {
88 STAILQ_ENTRY(bounce_zone) links;
89 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
90 int total_bpages;
91 int free_bpages;
92 int reserved_bpages;
93 int active_bpages;
94 int total_bounced;
95 int total_deferred;
96 int map_count;
97 bus_size_t alignment;
98 bus_addr_t lowaddr;
99 char zoneid[8];
100 char lowaddrid[20];
101 struct sysctl_ctx_list sysctl_tree;
102 struct sysctl_oid *sysctl_tree_top;
103 };
104
105 static struct mtx bounce_lock;
106 static int total_bpages;
107 static int busdma_zonecount;
108 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
109
110 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
111 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
112 "Total bounce pages");
113
114 struct bus_dmamap {
115 struct bp_list bpages;
116 int pagesneeded;
117 int pagesreserved;
118 bus_dma_tag_t dmat;
119 void *buf; /* unmapped buffer pointer */
120 bus_size_t buflen; /* unmapped buffer length */
121 bus_dmamap_callback_t *callback;
122 void *callback_arg;
123 STAILQ_ENTRY(bus_dmamap) links;
124 };
125
126 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
128 static struct bus_dmamap nobounce_dmamap;
129
130 static void init_bounce_pages(void *dummy);
131 static int alloc_bounce_zone(bus_dma_tag_t dmat);
132 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
133 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
134 int commit);
135 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
136 vm_offset_t vaddr, bus_size_t size);
137 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
138 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
139
140 /*
141 * Return true if a match is made.
142 *
143 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
144 *
145 * If paddr is within the bounds of the dma tag then call the filter callback
146 * to check for a match, if there is no filter callback then assume a match.
147 */
148 static __inline int
149 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
150 {
151 int retval;
152
153 retval = 0;
154
155 do {
156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
157 || ((paddr & (dmat->alignment - 1)) != 0))
158 && (dmat->filter == NULL
159 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
160 retval = 1;
161
162 dmat = dmat->parent;
163 } while (retval == 0 && dmat != NULL);
164 return (retval);
165 }
166
167 /*
168 * Convenience function for manipulating driver locks from busdma (during
169 * busdma_swi, for example). Drivers that don't provide their own locks
170 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
171 * non-mutex locking scheme don't have to use this at all.
172 */
173 void
174 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
175 {
176 struct mtx *dmtx;
177
178 dmtx = (struct mtx *)arg;
179 switch (op) {
180 case BUS_DMA_LOCK:
181 mtx_lock(dmtx);
182 break;
183 case BUS_DMA_UNLOCK:
184 mtx_unlock(dmtx);
185 break;
186 default:
187 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
188 }
189 }
190
191 /*
192 * dflt_lock should never get called. It gets put into the dma tag when
193 * lockfunc == NULL, which is only valid if the maps that are associated
194 * with the tag are meant to never be defered.
195 * XXX Should have a way to identify which driver is responsible here.
196 */
197 static void
198 dflt_lock(void *arg, bus_dma_lock_op_t op)
199 {
200 panic("driver error: busdma dflt_lock called");
201 }
202
203 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
204 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
205 /*
206 * Allocate a device specific dma_tag.
207 */
208 int
209 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
210 bus_size_t boundary, bus_addr_t lowaddr,
211 bus_addr_t highaddr, bus_dma_filter_t *filter,
212 void *filterarg, bus_size_t maxsize, int nsegments,
213 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
214 void *lockfuncarg, bus_dma_tag_t *dmat)
215 {
216 bus_dma_tag_t newtag;
217 int error = 0;
218
219 /* Basic sanity checking */
220 if (boundary != 0 && boundary < maxsegsz)
221 maxsegsz = boundary;
222
223 if (maxsegsz == 0) {
224 return (EINVAL);
225 }
226
227 /* Return a NULL tag on failure */
228 *dmat = NULL;
229
230 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
231 M_ZERO | M_NOWAIT);
232 if (newtag == NULL) {
233 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
234 __func__, newtag, 0, error);
235 return (ENOMEM);
236 }
237
238 newtag->parent = parent;
239 newtag->alignment = alignment;
240 newtag->boundary = boundary;
241 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
242 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (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 || (bz->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 bz->map_count++;
437 } else {
438 *mapp = NULL;
439 }
440 if (error == 0)
441 dmat->map_count++;
442 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
443 __func__, dmat, dmat->flags, error);
444 return (error);
445 }
446
447 /*
448 * Destroy a handle for mapping from kva/uva/physical
449 * address space into bus device space.
450 */
451 int
452 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
453 {
454 if (map != NULL && map != &nobounce_dmamap) {
455 if (STAILQ_FIRST(&map->bpages) != NULL) {
456 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
457 __func__, dmat, EBUSY);
458 return (EBUSY);
459 }
460 if (dmat->bounce_zone)
461 dmat->bounce_zone->map_count--;
462 free(map, M_DEVBUF);
463 }
464 dmat->map_count--;
465 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
466 return (0);
467 }
468
469
470 /*
471 * Allocate a piece of memory that can be efficiently mapped into
472 * bus device space based on the constraints lited in the dma tag.
473 * A dmamap to for use with dmamap_load is also allocated.
474 */
475 int
476 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
477 bus_dmamap_t *mapp)
478 {
479 int mflags;
480
481 if (flags & BUS_DMA_NOWAIT)
482 mflags = M_NOWAIT;
483 else
484 mflags = M_WAITOK;
485
486 /* If we succeed, no mapping/bouncing will be required */
487 *mapp = NULL;
488
489 if (dmat->segments == NULL) {
490 dmat->segments = (bus_dma_segment_t *)malloc(
491 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
492 mflags);
493 if (dmat->segments == NULL) {
494 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
495 __func__, dmat, dmat->flags, ENOMEM);
496 return (ENOMEM);
497 }
498 }
499 if (flags & BUS_DMA_ZERO)
500 mflags |= M_ZERO;
501
502 /*
503 * XXX:
504 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
505 * alignment guarantees of malloc need to be nailed down, and the
506 * code below should be rewritten to take that into account.
507 *
508 * In the meantime, we'll warn the user if malloc gets it wrong.
509 */
510 if ((dmat->maxsize <= PAGE_SIZE) &&
511 (dmat->alignment < dmat->maxsize) &&
512 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
513 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
514 } else {
515 /*
516 * XXX Use Contigmalloc until it is merged into this facility
517 * and handles multi-seg allocations. Nobody is doing
518 * multi-seg allocations yet though.
519 * XXX Certain AGP hardware does.
520 */
521 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
522 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
523 dmat->boundary);
524 }
525 if (*vaddr == NULL) {
526 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
527 __func__, dmat, dmat->flags, ENOMEM);
528 return (ENOMEM);
529 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
530 printf("bus_dmamem_alloc failed to align memory properly.\n");
531 }
532 if (flags & BUS_DMA_NOCACHE)
533 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
534 PAT_UNCACHEABLE);
535 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
536 __func__, dmat, dmat->flags, 0);
537 return (0);
538 }
539
540 /*
541 * Free a piece of memory and it's allociated dmamap, that was allocated
542 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
543 */
544 void
545 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
546 {
547 /*
548 * dmamem does not need to be bounced, so the map should be
549 * NULL
550 */
551 if (map != NULL)
552 panic("bus_dmamem_free: Invalid map freed\n");
553 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
554 if ((dmat->maxsize <= PAGE_SIZE) &&
555 (dmat->alignment < dmat->maxsize) &&
556 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
557 free(vaddr, M_DEVBUF);
558 else {
559 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
560 }
561 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
562 }
563
564 /*
565 * Utility function to load a linear buffer. lastaddrp holds state
566 * between invocations (for multiple-buffer loads). segp contains
567 * the starting segment on entrace, and the ending segment on exit.
568 * first indicates if this is the first invocation of this function.
569 */
570 static __inline int
571 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
572 bus_dmamap_t map,
573 void *buf, bus_size_t buflen,
574 pmap_t pmap,
575 int flags,
576 bus_addr_t *lastaddrp,
577 bus_dma_segment_t *segs,
578 int *segp,
579 int first)
580 {
581 bus_size_t sgsize;
582 bus_addr_t curaddr, lastaddr, baddr, bmask;
583 vm_offset_t vaddr;
584 bus_addr_t paddr;
585 int seg;
586
587 if (map == NULL)
588 map = &nobounce_dmamap;
589
590 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
591 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
592 vm_offset_t vendaddr;
593
594 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
595 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
596 dmat->boundary, dmat->alignment);
597 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
598 map, &nobounce_dmamap, map->pagesneeded);
599 /*
600 * Count the number of bounce pages
601 * needed in order to complete this transfer
602 */
603 vaddr = (vm_offset_t)buf;
604 vendaddr = (vm_offset_t)buf + buflen;
605
606 while (vaddr < vendaddr) {
607 bus_size_t sg_len;
608
609 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
610 if (pmap)
611 paddr = pmap_extract(pmap, vaddr);
612 else
613 paddr = pmap_kextract(vaddr);
614 if (run_filter(dmat, paddr) != 0) {
615 sg_len = roundup2(sg_len, dmat->alignment);
616 map->pagesneeded++;
617 }
618 vaddr += sg_len;
619 }
620 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
621 }
622
623 /* Reserve Necessary Bounce Pages */
624 if (map->pagesneeded != 0) {
625 mtx_lock(&bounce_lock);
626 if (flags & BUS_DMA_NOWAIT) {
627 if (reserve_bounce_pages(dmat, map, 0) != 0) {
628 mtx_unlock(&bounce_lock);
629 return (ENOMEM);
630 }
631 } else {
632 if (reserve_bounce_pages(dmat, map, 1) != 0) {
633 /* Queue us for resources */
634 map->dmat = dmat;
635 map->buf = buf;
636 map->buflen = buflen;
637 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
638 map, links);
639 mtx_unlock(&bounce_lock);
640 return (EINPROGRESS);
641 }
642 }
643 mtx_unlock(&bounce_lock);
644 }
645
646 vaddr = (vm_offset_t)buf;
647 lastaddr = *lastaddrp;
648 bmask = ~(dmat->boundary - 1);
649
650 for (seg = *segp; buflen > 0 ; ) {
651 bus_size_t max_sgsize;
652
653 /*
654 * Get the physical address for this segment.
655 */
656 if (pmap)
657 curaddr = pmap_extract(pmap, vaddr);
658 else
659 curaddr = pmap_kextract(vaddr);
660
661 /*
662 * Compute the segment size, and adjust counts.
663 */
664 max_sgsize = MIN(buflen, dmat->maxsegsz);
665 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
666 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
667 sgsize = roundup2(sgsize, dmat->alignment);
668 sgsize = MIN(sgsize, max_sgsize);
669 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
670 } else {
671 sgsize = MIN(sgsize, max_sgsize);
672 }
673
674 /*
675 * Make sure we don't cross any boundaries.
676 */
677 if (dmat->boundary > 0) {
678 baddr = (curaddr + dmat->boundary) & bmask;
679 if (sgsize > (baddr - curaddr))
680 sgsize = (baddr - curaddr);
681 }
682
683 /*
684 * Insert chunk into a segment, coalescing with
685 * previous segment if possible.
686 */
687 if (first) {
688 segs[seg].ds_addr = curaddr;
689 segs[seg].ds_len = sgsize;
690 first = 0;
691 } else {
692 if (curaddr == lastaddr &&
693 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
694 (dmat->boundary == 0 ||
695 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
696 segs[seg].ds_len += sgsize;
697 else {
698 if (++seg >= dmat->nsegments)
699 break;
700 segs[seg].ds_addr = curaddr;
701 segs[seg].ds_len = sgsize;
702 }
703 }
704
705 lastaddr = curaddr + sgsize;
706 vaddr += sgsize;
707 buflen -= sgsize;
708 }
709
710 *segp = seg;
711 *lastaddrp = lastaddr;
712
713 /*
714 * Did we fit?
715 */
716 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
717 }
718
719 /*
720 * Map the buffer buf into bus space using the dmamap map.
721 */
722 int
723 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
724 bus_size_t buflen, bus_dmamap_callback_t *callback,
725 void *callback_arg, int flags)
726 {
727 bus_addr_t lastaddr = 0;
728 int error, nsegs = 0;
729
730 if (map != NULL) {
731 flags |= BUS_DMA_WAITOK;
732 map->callback = callback;
733 map->callback_arg = callback_arg;
734 }
735
736 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
737 &lastaddr, dmat->segments, &nsegs, 1);
738
739 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
740 __func__, dmat, dmat->flags, error, nsegs + 1);
741
742 if (error == EINPROGRESS) {
743 return (error);
744 }
745
746 if (error)
747 (*callback)(callback_arg, dmat->segments, 0, error);
748 else
749 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
750
751 /*
752 * Return ENOMEM to the caller so that it can pass it up the stack.
753 * This error only happens when NOWAIT is set, so deferal is disabled.
754 */
755 if (error == ENOMEM)
756 return (error);
757
758 return (0);
759 }
760
761
762 /*
763 * Like _bus_dmamap_load(), but for mbufs.
764 */
765 int
766 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
767 struct mbuf *m0,
768 bus_dmamap_callback2_t *callback, void *callback_arg,
769 int flags)
770 {
771 int nsegs, error;
772
773 M_ASSERTPKTHDR(m0);
774
775 flags |= BUS_DMA_NOWAIT;
776 nsegs = 0;
777 error = 0;
778 if (m0->m_pkthdr.len <= dmat->maxsize) {
779 int first = 1;
780 bus_addr_t lastaddr = 0;
781 struct mbuf *m;
782
783 for (m = m0; m != NULL && error == 0; m = m->m_next) {
784 if (m->m_len > 0) {
785 error = _bus_dmamap_load_buffer(dmat, map,
786 m->m_data, m->m_len,
787 NULL, flags, &lastaddr,
788 dmat->segments, &nsegs, first);
789 first = 0;
790 }
791 }
792 } else {
793 error = EINVAL;
794 }
795
796 if (error) {
797 /* force "no valid mappings" in callback */
798 (*callback)(callback_arg, dmat->segments, 0, 0, error);
799 } else {
800 (*callback)(callback_arg, dmat->segments,
801 nsegs+1, m0->m_pkthdr.len, error);
802 }
803 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
804 __func__, dmat, dmat->flags, error, nsegs + 1);
805 return (error);
806 }
807
808 int
809 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
810 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
811 int flags)
812 {
813 int error;
814
815 M_ASSERTPKTHDR(m0);
816
817 flags |= BUS_DMA_NOWAIT;
818 *nsegs = 0;
819 error = 0;
820 if (m0->m_pkthdr.len <= dmat->maxsize) {
821 int first = 1;
822 bus_addr_t lastaddr = 0;
823 struct mbuf *m;
824
825 for (m = m0; m != NULL && error == 0; m = m->m_next) {
826 if (m->m_len > 0) {
827 error = _bus_dmamap_load_buffer(dmat, map,
828 m->m_data, m->m_len,
829 NULL, flags, &lastaddr,
830 segs, nsegs, first);
831 first = 0;
832 }
833 }
834 } else {
835 error = EINVAL;
836 }
837
838 /* XXX FIXME: Having to increment nsegs is really annoying */
839 ++*nsegs;
840 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
841 __func__, dmat, dmat->flags, error, *nsegs);
842 return (error);
843 }
844
845 /*
846 * Like _bus_dmamap_load(), but for uios.
847 */
848 int
849 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
850 struct uio *uio,
851 bus_dmamap_callback2_t *callback, void *callback_arg,
852 int flags)
853 {
854 bus_addr_t lastaddr = 0;
855 int nsegs, error, first, i;
856 bus_size_t resid;
857 struct iovec *iov;
858 pmap_t pmap;
859
860 flags |= BUS_DMA_NOWAIT;
861 resid = uio->uio_resid;
862 iov = uio->uio_iov;
863
864 if (uio->uio_segflg == UIO_USERSPACE) {
865 KASSERT(uio->uio_td != NULL,
866 ("bus_dmamap_load_uio: USERSPACE but no proc"));
867 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
868 } else
869 pmap = NULL;
870
871 nsegs = 0;
872 error = 0;
873 first = 1;
874 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
875 /*
876 * Now at the first iovec to load. Load each iovec
877 * until we have exhausted the residual count.
878 */
879 bus_size_t minlen =
880 resid < iov[i].iov_len ? resid : iov[i].iov_len;
881 caddr_t addr = (caddr_t) iov[i].iov_base;
882
883 if (minlen > 0) {
884 error = _bus_dmamap_load_buffer(dmat, map,
885 addr, minlen, pmap, flags, &lastaddr,
886 dmat->segments, &nsegs, first);
887 first = 0;
888
889 resid -= minlen;
890 }
891 }
892
893 if (error) {
894 /* force "no valid mappings" in callback */
895 (*callback)(callback_arg, dmat->segments, 0, 0, error);
896 } else {
897 (*callback)(callback_arg, dmat->segments,
898 nsegs+1, uio->uio_resid, error);
899 }
900 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
901 __func__, dmat, dmat->flags, error, nsegs + 1);
902 return (error);
903 }
904
905 /*
906 * Release the mapping held by map.
907 */
908 void
909 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
910 {
911 struct bounce_page *bpage;
912
913 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
914 STAILQ_REMOVE_HEAD(&map->bpages, links);
915 free_bounce_page(dmat, bpage);
916 }
917 }
918
919 void
920 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
921 {
922 struct bounce_page *bpage;
923
924 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
925 /*
926 * Handle data bouncing. We might also
927 * want to add support for invalidating
928 * the caches on broken hardware
929 */
930 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
931 "performing bounce", __func__, op, dmat, dmat->flags);
932
933 if (op & BUS_DMASYNC_PREWRITE) {
934 while (bpage != NULL) {
935 bcopy((void *)bpage->datavaddr,
936 (void *)bpage->vaddr,
937 bpage->datacount);
938 bpage = STAILQ_NEXT(bpage, links);
939 }
940 dmat->bounce_zone->total_bounced++;
941 }
942
943 if (op & BUS_DMASYNC_POSTREAD) {
944 while (bpage != NULL) {
945 bcopy((void *)bpage->vaddr,
946 (void *)bpage->datavaddr,
947 bpage->datacount);
948 bpage = STAILQ_NEXT(bpage, links);
949 }
950 dmat->bounce_zone->total_bounced++;
951 }
952 }
953 }
954
955 static void
956 init_bounce_pages(void *dummy __unused)
957 {
958
959 total_bpages = 0;
960 STAILQ_INIT(&bounce_zone_list);
961 STAILQ_INIT(&bounce_map_waitinglist);
962 STAILQ_INIT(&bounce_map_callbacklist);
963 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
964 }
965 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
966
967 static struct sysctl_ctx_list *
968 busdma_sysctl_tree(struct bounce_zone *bz)
969 {
970 return (&bz->sysctl_tree);
971 }
972
973 static struct sysctl_oid *
974 busdma_sysctl_tree_top(struct bounce_zone *bz)
975 {
976 return (bz->sysctl_tree_top);
977 }
978
979 static int
980 alloc_bounce_zone(bus_dma_tag_t dmat)
981 {
982 struct bounce_zone *bz;
983
984 /* Check to see if we already have a suitable zone */
985 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
986 if ((dmat->alignment <= bz->alignment)
987 && (dmat->lowaddr >= bz->lowaddr)) {
988 dmat->bounce_zone = bz;
989 return (0);
990 }
991 }
992
993 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
994 M_NOWAIT | M_ZERO)) == NULL)
995 return (ENOMEM);
996
997 STAILQ_INIT(&bz->bounce_page_list);
998 bz->free_bpages = 0;
999 bz->reserved_bpages = 0;
1000 bz->active_bpages = 0;
1001 bz->lowaddr = dmat->lowaddr;
1002 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1003 bz->map_count = 0;
1004 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1005 busdma_zonecount++;
1006 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1007 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1008 dmat->bounce_zone = bz;
1009
1010 sysctl_ctx_init(&bz->sysctl_tree);
1011 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1012 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1013 CTLFLAG_RD, 0, "");
1014 if (bz->sysctl_tree_top == NULL) {
1015 sysctl_ctx_free(&bz->sysctl_tree);
1016 return (0); /* XXX error code? */
1017 }
1018
1019 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1020 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1021 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1022 "Total bounce pages");
1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1025 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1026 "Free bounce pages");
1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1029 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1030 "Reserved bounce pages");
1031 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1032 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1033 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1034 "Active bounce pages");
1035 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1036 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1037 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1038 "Total bounce requests");
1039 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1040 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1041 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1042 "Total bounce requests that were deferred");
1043 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1045 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1046 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1047 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1048 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1049
1050 return (0);
1051 }
1052
1053 static int
1054 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1055 {
1056 struct bounce_zone *bz;
1057 int count;
1058
1059 bz = dmat->bounce_zone;
1060 count = 0;
1061 while (numpages > 0) {
1062 struct bounce_page *bpage;
1063
1064 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1065 M_NOWAIT | M_ZERO);
1066
1067 if (bpage == NULL)
1068 break;
1069 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1070 M_NOWAIT, 0ul,
1071 bz->lowaddr,
1072 PAGE_SIZE,
1073 0);
1074 if (bpage->vaddr == 0) {
1075 free(bpage, M_DEVBUF);
1076 break;
1077 }
1078 bpage->busaddr = pmap_kextract(bpage->vaddr);
1079 mtx_lock(&bounce_lock);
1080 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1081 total_bpages++;
1082 bz->total_bpages++;
1083 bz->free_bpages++;
1084 mtx_unlock(&bounce_lock);
1085 count++;
1086 numpages--;
1087 }
1088 return (count);
1089 }
1090
1091 static int
1092 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1093 {
1094 struct bounce_zone *bz;
1095 int pages;
1096
1097 mtx_assert(&bounce_lock, MA_OWNED);
1098 bz = dmat->bounce_zone;
1099 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1100 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1101 return (map->pagesneeded - (map->pagesreserved + pages));
1102 bz->free_bpages -= pages;
1103 bz->reserved_bpages += pages;
1104 map->pagesreserved += pages;
1105 pages = map->pagesneeded - map->pagesreserved;
1106
1107 return (pages);
1108 }
1109
1110 static bus_addr_t
1111 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1112 bus_size_t size)
1113 {
1114 struct bounce_zone *bz;
1115 struct bounce_page *bpage;
1116
1117 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1118 KASSERT(map != NULL && map != &nobounce_dmamap,
1119 ("add_bounce_page: bad map %p", map));
1120
1121 bz = dmat->bounce_zone;
1122 if (map->pagesneeded == 0)
1123 panic("add_bounce_page: map doesn't need any pages");
1124 map->pagesneeded--;
1125
1126 if (map->pagesreserved == 0)
1127 panic("add_bounce_page: map doesn't need any pages");
1128 map->pagesreserved--;
1129
1130 mtx_lock(&bounce_lock);
1131 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1132 if (bpage == NULL)
1133 panic("add_bounce_page: free page list is empty");
1134
1135 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1136 bz->reserved_bpages--;
1137 bz->active_bpages++;
1138 mtx_unlock(&bounce_lock);
1139
1140 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1141 /* Page offset needs to be preserved. */
1142 bpage->vaddr |= vaddr & PAGE_MASK;
1143 bpage->busaddr |= vaddr & PAGE_MASK;
1144 }
1145 bpage->datavaddr = vaddr;
1146 bpage->datacount = size;
1147 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1148 return (bpage->busaddr);
1149 }
1150
1151 static void
1152 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1153 {
1154 struct bus_dmamap *map;
1155 struct bounce_zone *bz;
1156
1157 bz = dmat->bounce_zone;
1158 bpage->datavaddr = 0;
1159 bpage->datacount = 0;
1160 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1161 /*
1162 * Reset the bounce page to start at offset 0. Other uses
1163 * of this bounce page may need to store a full page of
1164 * data and/or assume it starts on a page boundary.
1165 */
1166 bpage->vaddr &= ~PAGE_MASK;
1167 bpage->busaddr &= ~PAGE_MASK;
1168 }
1169
1170 mtx_lock(&bounce_lock);
1171 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1172 bz->free_bpages++;
1173 bz->active_bpages--;
1174 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1175 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1176 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1177 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1178 map, links);
1179 busdma_swi_pending = 1;
1180 bz->total_deferred++;
1181 swi_sched(vm_ih, 0);
1182 }
1183 }
1184 mtx_unlock(&bounce_lock);
1185 }
1186
1187 void
1188 busdma_swi(void)
1189 {
1190 bus_dma_tag_t dmat;
1191 struct bus_dmamap *map;
1192
1193 mtx_lock(&bounce_lock);
1194 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1195 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1196 mtx_unlock(&bounce_lock);
1197 dmat = map->dmat;
1198 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1199 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1200 map->callback, map->callback_arg, /*flags*/0);
1201 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1202 mtx_lock(&bounce_lock);
1203 }
1204 mtx_unlock(&bounce_lock);
1205 }
Cache object: 09f1d23cf403ba09b01284e50a52363f
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