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 /*
28 * From amd64/busdma_machdep.c, r204214
29 */
30
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
37 #include <sys/bus.h>
38 #include <sys/interrupt.h>
39 #include <sys/kernel.h>
40 #include <sys/ktr.h>
41 #include <sys/lock.h>
42 #include <sys/proc.h>
43 #include <sys/mutex.h>
44 #include <sys/mbuf.h>
45 #include <sys/uio.h>
46 #include <sys/sysctl.h>
47
48 #include <vm/vm.h>
49 #include <vm/vm_page.h>
50 #include <vm/vm_map.h>
51
52 #include <machine/atomic.h>
53 #include <machine/bus.h>
54 #include <machine/md_var.h>
55
56 #define MAX_BPAGES 8192
57
58 struct bounce_zone;
59
60 struct bus_dma_tag {
61 bus_dma_tag_t parent;
62 bus_size_t alignment;
63 bus_size_t boundary;
64 bus_addr_t lowaddr;
65 bus_addr_t highaddr;
66 bus_dma_filter_t *filter;
67 void *filterarg;
68 bus_size_t maxsize;
69 u_int nsegments;
70 bus_size_t maxsegsz;
71 int flags;
72 int ref_count;
73 int map_count;
74 bus_dma_lock_t *lockfunc;
75 void *lockfuncarg;
76 bus_dma_segment_t *segments;
77 struct bounce_zone *bounce_zone;
78 };
79
80 struct bounce_page {
81 vm_offset_t vaddr; /* kva of bounce buffer */
82 bus_addr_t busaddr; /* Physical address */
83 vm_offset_t datavaddr; /* kva of client data */
84 bus_size_t datacount; /* client data count */
85 STAILQ_ENTRY(bounce_page) links;
86 };
87
88 int busdma_swi_pending;
89
90 struct bounce_zone {
91 STAILQ_ENTRY(bounce_zone) links;
92 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
93 int total_bpages;
94 int free_bpages;
95 int reserved_bpages;
96 int active_bpages;
97 int total_bounced;
98 int total_deferred;
99 int map_count;
100 bus_size_t alignment;
101 bus_addr_t lowaddr;
102 char zoneid[8];
103 char lowaddrid[20];
104 struct sysctl_ctx_list sysctl_tree;
105 struct sysctl_oid *sysctl_tree_top;
106 };
107
108 static struct mtx bounce_lock;
109 static int total_bpages;
110 static int busdma_zonecount;
111 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
112
113 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
114 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
115 "Total bounce pages");
116
117 struct bus_dmamap {
118 struct bp_list bpages;
119 int pagesneeded;
120 int pagesreserved;
121 bus_dma_tag_t dmat;
122 void *buf; /* unmapped buffer pointer */
123 bus_size_t buflen; /* unmapped buffer length */
124 bus_dmamap_callback_t *callback;
125 void *callback_arg;
126 STAILQ_ENTRY(bus_dmamap) links;
127 };
128
129 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
130 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
131 static struct bus_dmamap nobounce_dmamap;
132
133 static void init_bounce_pages(void *dummy);
134 static int alloc_bounce_zone(bus_dma_tag_t dmat);
135 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
136 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
137 int commit);
138 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
139 vm_offset_t vaddr, bus_size_t size);
140 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
141 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
142
143 /*
144 * Return true if a match is made.
145 *
146 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
147 *
148 * If paddr is within the bounds of the dma tag then call the filter callback
149 * to check for a match, if there is no filter callback then assume a match.
150 */
151 static __inline int
152 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
153 {
154 int retval;
155
156 retval = 0;
157
158 do {
159 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
160 || ((paddr & (dmat->alignment - 1)) != 0))
161 && (dmat->filter == NULL
162 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
163 retval = 1;
164
165 dmat = dmat->parent;
166 } while (retval == 0 && dmat != NULL);
167 return (retval);
168 }
169
170 /*
171 * Convenience function for manipulating driver locks from busdma (during
172 * busdma_swi, for example). Drivers that don't provide their own locks
173 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
174 * non-mutex locking scheme don't have to use this at all.
175 */
176 void
177 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
178 {
179 struct mtx *dmtx;
180
181 dmtx = (struct mtx *)arg;
182 switch (op) {
183 case BUS_DMA_LOCK:
184 mtx_lock(dmtx);
185 break;
186 case BUS_DMA_UNLOCK:
187 mtx_unlock(dmtx);
188 break;
189 default:
190 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
191 }
192 }
193
194 /*
195 * dflt_lock should never get called. It gets put into the dma tag when
196 * lockfunc == NULL, which is only valid if the maps that are associated
197 * with the tag are meant to never be defered.
198 * XXX Should have a way to identify which driver is responsible here.
199 */
200 static void
201 dflt_lock(void *arg, bus_dma_lock_op_t op)
202 {
203 panic("driver error: busdma dflt_lock called");
204 }
205
206 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
207 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
208 /*
209 * Allocate a device specific dma_tag.
210 */
211 int
212 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
213 bus_size_t boundary, bus_addr_t lowaddr,
214 bus_addr_t highaddr, bus_dma_filter_t *filter,
215 void *filterarg, bus_size_t maxsize, int nsegments,
216 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
217 void *lockfuncarg, bus_dma_tag_t *dmat)
218 {
219 bus_dma_tag_t newtag;
220 int error = 0;
221
222 /* Basic sanity checking */
223 if (boundary != 0 && boundary < maxsegsz)
224 maxsegsz = boundary;
225
226 if (maxsegsz == 0) {
227 return (EINVAL);
228 }
229
230 /* Return a NULL tag on failure */
231 *dmat = NULL;
232
233 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
234 M_ZERO | M_NOWAIT);
235 if (newtag == NULL) {
236 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
237 __func__, newtag, 0, error);
238 return (ENOMEM);
239 }
240
241 newtag->parent = parent;
242 newtag->alignment = alignment;
243 newtag->boundary = boundary;
244 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
245 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
246 newtag->filter = filter;
247 newtag->filterarg = filterarg;
248 newtag->maxsize = maxsize;
249 newtag->nsegments = nsegments;
250 newtag->maxsegsz = maxsegsz;
251 newtag->flags = flags;
252 newtag->ref_count = 1; /* Count ourself */
253 newtag->map_count = 0;
254 if (lockfunc != NULL) {
255 newtag->lockfunc = lockfunc;
256 newtag->lockfuncarg = lockfuncarg;
257 } else {
258 newtag->lockfunc = dflt_lock;
259 newtag->lockfuncarg = NULL;
260 }
261 newtag->segments = NULL;
262
263 /* Take into account any restrictions imposed by our parent tag */
264 if (parent != NULL) {
265 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
266 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
267 if (newtag->boundary == 0)
268 newtag->boundary = parent->boundary;
269 else if (parent->boundary != 0)
270 newtag->boundary = MIN(parent->boundary,
271 newtag->boundary);
272 if (newtag->filter == NULL) {
273 /*
274 * Short circuit looking at our parent directly
275 * since we have encapsulated all of its information
276 */
277 newtag->filter = parent->filter;
278 newtag->filterarg = parent->filterarg;
279 newtag->parent = parent->parent;
280 }
281 if (newtag->parent != NULL)
282 atomic_add_int(&parent->ref_count, 1);
283 }
284
285 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
286 || newtag->alignment > 1)
287 newtag->flags |= BUS_DMA_COULD_BOUNCE;
288
289 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
290 (flags & BUS_DMA_ALLOCNOW) != 0) {
291 struct bounce_zone *bz;
292
293 /* Must bounce */
294
295 if ((error = alloc_bounce_zone(newtag)) != 0) {
296 free(newtag, M_DEVBUF);
297 return (error);
298 }
299 bz = newtag->bounce_zone;
300
301 if (ptoa(bz->total_bpages) < maxsize) {
302 int pages;
303
304 pages = atop(maxsize) - bz->total_bpages;
305
306 /* Add pages to our bounce pool */
307 if (alloc_bounce_pages(newtag, pages) < pages)
308 error = ENOMEM;
309 }
310 /* Performed initial allocation */
311 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
312 }
313
314 if (error != 0) {
315 free(newtag, M_DEVBUF);
316 } else {
317 *dmat = newtag;
318 }
319 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
320 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
321 return (error);
322 }
323
324 int
325 bus_dma_tag_destroy(bus_dma_tag_t dmat)
326 {
327 bus_dma_tag_t dmat_copy;
328 int error;
329
330 error = 0;
331 dmat_copy = dmat;
332
333 if (dmat != NULL) {
334
335 if (dmat->map_count != 0) {
336 error = EBUSY;
337 goto out;
338 }
339
340 while (dmat != NULL) {
341 bus_dma_tag_t parent;
342
343 parent = dmat->parent;
344 atomic_subtract_int(&dmat->ref_count, 1);
345 if (dmat->ref_count == 0) {
346 if (dmat->segments != NULL)
347 free(dmat->segments, M_DEVBUF);
348 free(dmat, M_DEVBUF);
349 /*
350 * Last reference count, so
351 * release our reference
352 * count on our parent.
353 */
354 dmat = parent;
355 } else
356 dmat = NULL;
357 }
358 }
359 out:
360 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
361 return (error);
362 }
363
364 /*
365 * Allocate a handle for mapping from kva/uva/physical
366 * address space into bus device space.
367 */
368 int
369 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
370 {
371 int error;
372
373 error = 0;
374
375 if (dmat->segments == NULL) {
376 dmat->segments = (bus_dma_segment_t *)malloc(
377 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
378 M_NOWAIT);
379 if (dmat->segments == NULL) {
380 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
381 __func__, dmat, ENOMEM);
382 return (ENOMEM);
383 }
384 }
385
386 /*
387 * Bouncing might be required if the driver asks for an active
388 * exclusion region, a data alignment that is stricter than 1, and/or
389 * an active address boundary.
390 */
391 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
392
393 /* Must bounce */
394 struct bounce_zone *bz;
395 int maxpages;
396
397 if (dmat->bounce_zone == NULL) {
398 if ((error = alloc_bounce_zone(dmat)) != 0)
399 return (error);
400 }
401 bz = dmat->bounce_zone;
402
403 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
404 M_NOWAIT | M_ZERO);
405 if (*mapp == NULL) {
406 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
407 __func__, dmat, ENOMEM);
408 return (ENOMEM);
409 }
410
411 /* Initialize the new map */
412 STAILQ_INIT(&((*mapp)->bpages));
413
414 /*
415 * Attempt to add pages to our pool on a per-instance
416 * basis up to a sane limit.
417 */
418 if (dmat->alignment > 1)
419 maxpages = MAX_BPAGES;
420 else
421 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
422 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
423 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
424 int pages;
425
426 pages = MAX(atop(dmat->maxsize), 1);
427 pages = MIN(maxpages - bz->total_bpages, pages);
428 pages = MAX(pages, 1);
429 if (alloc_bounce_pages(dmat, pages) < pages)
430 error = ENOMEM;
431
432 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
433 if (error == 0)
434 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
435 } else {
436 error = 0;
437 }
438 }
439 bz->map_count++;
440 } else {
441 *mapp = NULL;
442 }
443 if (error == 0)
444 dmat->map_count++;
445 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
446 __func__, dmat, dmat->flags, error);
447 return (error);
448 }
449
450 /*
451 * Destroy a handle for mapping from kva/uva/physical
452 * address space into bus device space.
453 */
454 int
455 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
456 {
457 if (map != NULL && map != &nobounce_dmamap) {
458 if (STAILQ_FIRST(&map->bpages) != NULL) {
459 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
460 __func__, dmat, EBUSY);
461 return (EBUSY);
462 }
463 if (dmat->bounce_zone)
464 dmat->bounce_zone->map_count--;
465 free(map, M_DEVBUF);
466 }
467 dmat->map_count--;
468 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
469 return (0);
470 }
471
472
473 /*
474 * Allocate a piece of memory that can be efficiently mapped into
475 * bus device space based on the constraints lited in the dma tag.
476 * A dmamap to for use with dmamap_load is also allocated.
477 */
478 int
479 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
480 bus_dmamap_t *mapp)
481 {
482 int mflags;
483
484 if (flags & BUS_DMA_NOWAIT)
485 mflags = M_NOWAIT;
486 else
487 mflags = M_WAITOK;
488
489 /* If we succeed, no mapping/bouncing will be required */
490 *mapp = NULL;
491
492 if (dmat->segments == NULL) {
493 dmat->segments = (bus_dma_segment_t *)malloc(
494 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
495 mflags);
496 if (dmat->segments == NULL) {
497 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
498 __func__, dmat, dmat->flags, ENOMEM);
499 return (ENOMEM);
500 }
501 }
502 if (flags & BUS_DMA_ZERO)
503 mflags |= M_ZERO;
504
505 /*
506 * XXX:
507 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
508 * alignment guarantees of malloc need to be nailed down, and the
509 * code below should be rewritten to take that into account.
510 *
511 * In the meantime, we'll warn the user if malloc gets it wrong.
512 */
513 if ((dmat->maxsize <= PAGE_SIZE) &&
514 (dmat->alignment < dmat->maxsize) &&
515 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
516 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
517 } else {
518 /*
519 * XXX Use Contigmalloc until it is merged into this facility
520 * and handles multi-seg allocations. Nobody is doing
521 * multi-seg allocations yet though.
522 * XXX Certain AGP hardware does.
523 */
524 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
525 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
526 dmat->boundary);
527 }
528 if (*vaddr == NULL) {
529 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
530 __func__, dmat, dmat->flags, ENOMEM);
531 return (ENOMEM);
532 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
533 printf("bus_dmamem_alloc failed to align memory properly.\n");
534 }
535 #ifdef NOTYET
536 if (flags & BUS_DMA_NOCACHE)
537 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
538 PAT_UNCACHEABLE);
539 #endif
540 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
541 __func__, dmat, dmat->flags, 0);
542 return (0);
543 }
544
545 /*
546 * Free a piece of memory and it's allociated dmamap, that was allocated
547 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
548 */
549 void
550 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
551 {
552 /*
553 * dmamem does not need to be bounced, so the map should be
554 * NULL
555 */
556 if (map != NULL)
557 panic("bus_dmamem_free: Invalid map freed\n");
558 #ifdef NOTYET
559 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
560 #endif
561 if ((dmat->maxsize <= PAGE_SIZE) &&
562 (dmat->alignment < dmat->maxsize) &&
563 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
564 free(vaddr, M_DEVBUF);
565 else {
566 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
567 }
568 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
569 }
570
571 /*
572 * Utility function to load a linear buffer. lastaddrp holds state
573 * between invocations (for multiple-buffer loads). segp contains
574 * the starting segment on entrance, and the ending segment on exit.
575 * first indicates if this is the first invocation of this function.
576 */
577 static __inline int
578 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
579 bus_dmamap_t map,
580 void *buf, bus_size_t buflen,
581 pmap_t pmap,
582 int flags,
583 bus_addr_t *lastaddrp,
584 bus_dma_segment_t *segs,
585 int *segp,
586 int first)
587 {
588 bus_size_t sgsize;
589 bus_addr_t curaddr, lastaddr, baddr, bmask;
590 vm_offset_t vaddr;
591 bus_addr_t paddr;
592 int seg;
593
594 if (map == NULL)
595 map = &nobounce_dmamap;
596
597 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
598 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
599 vm_offset_t vendaddr;
600
601 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
602 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
603 dmat->boundary, dmat->alignment);
604 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
605 map, &nobounce_dmamap, map->pagesneeded);
606 /*
607 * Count the number of bounce pages
608 * needed in order to complete this transfer
609 */
610 vaddr = (vm_offset_t)buf;
611 vendaddr = (vm_offset_t)buf + buflen;
612
613 while (vaddr < vendaddr) {
614 bus_size_t sg_len;
615
616 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
617 if (pmap)
618 paddr = pmap_extract(pmap, vaddr);
619 else
620 paddr = pmap_kextract(vaddr);
621 if (run_filter(dmat, paddr) != 0) {
622 sg_len = roundup2(sg_len, dmat->alignment);
623 map->pagesneeded++;
624 }
625 vaddr += sg_len;
626 }
627 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
628 }
629
630 /* Reserve Necessary Bounce Pages */
631 if (map->pagesneeded != 0) {
632 mtx_lock(&bounce_lock);
633 if (flags & BUS_DMA_NOWAIT) {
634 if (reserve_bounce_pages(dmat, map, 0) != 0) {
635 mtx_unlock(&bounce_lock);
636 return (ENOMEM);
637 }
638 } else {
639 if (reserve_bounce_pages(dmat, map, 1) != 0) {
640 /* Queue us for resources */
641 map->dmat = dmat;
642 map->buf = buf;
643 map->buflen = buflen;
644 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
645 map, links);
646 mtx_unlock(&bounce_lock);
647 return (EINPROGRESS);
648 }
649 }
650 mtx_unlock(&bounce_lock);
651 }
652
653 vaddr = (vm_offset_t)buf;
654 lastaddr = *lastaddrp;
655 bmask = ~(dmat->boundary - 1);
656
657 for (seg = *segp; buflen > 0 ; ) {
658 bus_size_t max_sgsize;
659
660 /*
661 * Get the physical address for this segment.
662 */
663 if (pmap)
664 curaddr = pmap_extract(pmap, vaddr);
665 else
666 curaddr = pmap_kextract(vaddr);
667
668 /*
669 * Compute the segment size, and adjust counts.
670 */
671 max_sgsize = MIN(buflen, dmat->maxsegsz);
672 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
673 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
674 sgsize = roundup2(sgsize, dmat->alignment);
675 sgsize = MIN(sgsize, max_sgsize);
676 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
677 } else {
678 sgsize = MIN(sgsize, max_sgsize);
679 }
680
681 /*
682 * Make sure we don't cross any boundaries.
683 */
684 if (dmat->boundary > 0) {
685 baddr = (curaddr + dmat->boundary) & bmask;
686 if (sgsize > (baddr - curaddr))
687 sgsize = (baddr - curaddr);
688 }
689
690 /*
691 * Insert chunk into a segment, coalescing with
692 * previous segment if possible.
693 */
694 if (first) {
695 segs[seg].ds_addr = curaddr;
696 segs[seg].ds_len = sgsize;
697 first = 0;
698 } else {
699 if (curaddr == lastaddr &&
700 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
701 (dmat->boundary == 0 ||
702 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
703 segs[seg].ds_len += sgsize;
704 else {
705 if (++seg >= dmat->nsegments)
706 break;
707 segs[seg].ds_addr = curaddr;
708 segs[seg].ds_len = sgsize;
709 }
710 }
711
712 lastaddr = curaddr + sgsize;
713 vaddr += sgsize;
714 buflen -= sgsize;
715 }
716
717 *segp = seg;
718 *lastaddrp = lastaddr;
719
720 /*
721 * Did we fit?
722 */
723 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
724 }
725
726 /*
727 * Map the buffer buf into bus space using the dmamap map.
728 */
729 int
730 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
731 bus_size_t buflen, bus_dmamap_callback_t *callback,
732 void *callback_arg, int flags)
733 {
734 bus_addr_t lastaddr = 0;
735 int error, nsegs = 0;
736
737 if (map != NULL) {
738 flags |= BUS_DMA_WAITOK;
739 map->callback = callback;
740 map->callback_arg = callback_arg;
741 }
742
743 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
744 &lastaddr, dmat->segments, &nsegs, 1);
745
746 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
747 __func__, dmat, dmat->flags, error, nsegs + 1);
748
749 if (error == EINPROGRESS) {
750 return (error);
751 }
752
753 if (error)
754 (*callback)(callback_arg, dmat->segments, 0, error);
755 else
756 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
757
758 /*
759 * Return ENOMEM to the caller so that it can pass it up the stack.
760 * This error only happens when NOWAIT is set, so deferal is disabled.
761 */
762 if (error == ENOMEM)
763 return (error);
764
765 return (0);
766 }
767
768
769 /*
770 * Like _bus_dmamap_load(), but for mbufs.
771 */
772 int
773 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
774 struct mbuf *m0,
775 bus_dmamap_callback2_t *callback, void *callback_arg,
776 int flags)
777 {
778 int nsegs, error;
779
780 M_ASSERTPKTHDR(m0);
781
782 flags |= BUS_DMA_NOWAIT;
783 nsegs = 0;
784 error = 0;
785 if (m0->m_pkthdr.len <= dmat->maxsize) {
786 int first = 1;
787 bus_addr_t lastaddr = 0;
788 struct mbuf *m;
789
790 for (m = m0; m != NULL && error == 0; m = m->m_next) {
791 if (m->m_len > 0) {
792 error = _bus_dmamap_load_buffer(dmat, map,
793 m->m_data, m->m_len,
794 NULL, flags, &lastaddr,
795 dmat->segments, &nsegs, first);
796 first = 0;
797 }
798 }
799 } else {
800 error = EINVAL;
801 }
802
803 if (error) {
804 /* force "no valid mappings" in callback */
805 (*callback)(callback_arg, dmat->segments, 0, 0, error);
806 } else {
807 (*callback)(callback_arg, dmat->segments,
808 nsegs+1, m0->m_pkthdr.len, error);
809 }
810 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
811 __func__, dmat, dmat->flags, error, nsegs + 1);
812 return (error);
813 }
814
815 int
816 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
817 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
818 int flags)
819 {
820 int error;
821
822 M_ASSERTPKTHDR(m0);
823
824 flags |= BUS_DMA_NOWAIT;
825 *nsegs = 0;
826 error = 0;
827 if (m0->m_pkthdr.len <= dmat->maxsize) {
828 int first = 1;
829 bus_addr_t lastaddr = 0;
830 struct mbuf *m;
831
832 for (m = m0; m != NULL && error == 0; m = m->m_next) {
833 if (m->m_len > 0) {
834 error = _bus_dmamap_load_buffer(dmat, map,
835 m->m_data, m->m_len,
836 NULL, flags, &lastaddr,
837 segs, nsegs, first);
838 first = 0;
839 }
840 }
841 } else {
842 error = EINVAL;
843 }
844
845 /* XXX FIXME: Having to increment nsegs is really annoying */
846 ++*nsegs;
847 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
848 __func__, dmat, dmat->flags, error, *nsegs);
849 return (error);
850 }
851
852 /*
853 * Like _bus_dmamap_load(), but for uios.
854 */
855 int
856 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
857 struct uio *uio,
858 bus_dmamap_callback2_t *callback, void *callback_arg,
859 int flags)
860 {
861 bus_addr_t lastaddr = 0;
862 int nsegs, error, first, i;
863 bus_size_t resid;
864 struct iovec *iov;
865 pmap_t pmap;
866
867 flags |= BUS_DMA_NOWAIT;
868 resid = uio->uio_resid;
869 iov = uio->uio_iov;
870
871 if (uio->uio_segflg == UIO_USERSPACE) {
872 KASSERT(uio->uio_td != NULL,
873 ("bus_dmamap_load_uio: USERSPACE but no proc"));
874 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
875 } else
876 pmap = NULL;
877
878 nsegs = 0;
879 error = 0;
880 first = 1;
881 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
882 /*
883 * Now at the first iovec to load. Load each iovec
884 * until we have exhausted the residual count.
885 */
886 bus_size_t minlen =
887 resid < iov[i].iov_len ? resid : iov[i].iov_len;
888 caddr_t addr = (caddr_t) iov[i].iov_base;
889
890 if (minlen > 0) {
891 error = _bus_dmamap_load_buffer(dmat, map,
892 addr, minlen, pmap, flags, &lastaddr,
893 dmat->segments, &nsegs, first);
894 first = 0;
895
896 resid -= minlen;
897 }
898 }
899
900 if (error) {
901 /* force "no valid mappings" in callback */
902 (*callback)(callback_arg, dmat->segments, 0, 0, error);
903 } else {
904 (*callback)(callback_arg, dmat->segments,
905 nsegs+1, uio->uio_resid, error);
906 }
907 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
908 __func__, dmat, dmat->flags, error, nsegs + 1);
909 return (error);
910 }
911
912 /*
913 * Release the mapping held by map.
914 */
915 void
916 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
917 {
918 struct bounce_page *bpage;
919
920 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
921 STAILQ_REMOVE_HEAD(&map->bpages, links);
922 free_bounce_page(dmat, bpage);
923 }
924 }
925
926 void
927 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
928 {
929 struct bounce_page *bpage;
930
931 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
932 /*
933 * Handle data bouncing. We might also
934 * want to add support for invalidating
935 * the caches on broken hardware
936 */
937 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
938 "performing bounce", __func__, op, dmat, dmat->flags);
939
940 if (op & BUS_DMASYNC_PREWRITE) {
941 while (bpage != NULL) {
942 bcopy((void *)bpage->datavaddr,
943 (void *)bpage->vaddr,
944 bpage->datacount);
945 bpage = STAILQ_NEXT(bpage, links);
946 }
947 dmat->bounce_zone->total_bounced++;
948 }
949
950 if (op & BUS_DMASYNC_POSTREAD) {
951 while (bpage != NULL) {
952 bcopy((void *)bpage->vaddr,
953 (void *)bpage->datavaddr,
954 bpage->datacount);
955 bpage = STAILQ_NEXT(bpage, links);
956 }
957 dmat->bounce_zone->total_bounced++;
958 }
959 }
960 }
961
962 static void
963 init_bounce_pages(void *dummy __unused)
964 {
965
966 total_bpages = 0;
967 STAILQ_INIT(&bounce_zone_list);
968 STAILQ_INIT(&bounce_map_waitinglist);
969 STAILQ_INIT(&bounce_map_callbacklist);
970 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
971 }
972 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
973
974 static struct sysctl_ctx_list *
975 busdma_sysctl_tree(struct bounce_zone *bz)
976 {
977 return (&bz->sysctl_tree);
978 }
979
980 static struct sysctl_oid *
981 busdma_sysctl_tree_top(struct bounce_zone *bz)
982 {
983 return (bz->sysctl_tree_top);
984 }
985
986 static int
987 alloc_bounce_zone(bus_dma_tag_t dmat)
988 {
989 struct bounce_zone *bz;
990
991 /* Check to see if we already have a suitable zone */
992 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
993 if ((dmat->alignment <= bz->alignment)
994 && (dmat->lowaddr >= bz->lowaddr)) {
995 dmat->bounce_zone = bz;
996 return (0);
997 }
998 }
999
1000 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1001 M_NOWAIT | M_ZERO)) == NULL)
1002 return (ENOMEM);
1003
1004 STAILQ_INIT(&bz->bounce_page_list);
1005 bz->free_bpages = 0;
1006 bz->reserved_bpages = 0;
1007 bz->active_bpages = 0;
1008 bz->lowaddr = dmat->lowaddr;
1009 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1010 bz->map_count = 0;
1011 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1012 busdma_zonecount++;
1013 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1014 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1015 dmat->bounce_zone = bz;
1016
1017 sysctl_ctx_init(&bz->sysctl_tree);
1018 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1019 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1020 CTLFLAG_RD, 0, "");
1021 if (bz->sysctl_tree_top == NULL) {
1022 sysctl_ctx_free(&bz->sysctl_tree);
1023 return (0); /* XXX error code? */
1024 }
1025
1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1028 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1029 "Total bounce pages");
1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1032 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1033 "Free bounce pages");
1034 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1035 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1036 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1037 "Reserved bounce pages");
1038 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1039 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1040 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1041 "Active bounce pages");
1042 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1043 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1044 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1045 "Total bounce requests");
1046 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1047 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1048 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1049 "Total bounce requests that were deferred");
1050 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1052 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1053 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1054 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1055 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1056
1057 return (0);
1058 }
1059
1060 static int
1061 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1062 {
1063 struct bounce_zone *bz;
1064 int count;
1065
1066 bz = dmat->bounce_zone;
1067 count = 0;
1068 while (numpages > 0) {
1069 struct bounce_page *bpage;
1070
1071 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1072 M_NOWAIT | M_ZERO);
1073
1074 if (bpage == NULL)
1075 break;
1076 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1077 M_NOWAIT, 0ul,
1078 bz->lowaddr,
1079 PAGE_SIZE,
1080 0);
1081 if (bpage->vaddr == 0) {
1082 free(bpage, M_DEVBUF);
1083 break;
1084 }
1085 bpage->busaddr = pmap_kextract(bpage->vaddr);
1086 mtx_lock(&bounce_lock);
1087 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1088 total_bpages++;
1089 bz->total_bpages++;
1090 bz->free_bpages++;
1091 mtx_unlock(&bounce_lock);
1092 count++;
1093 numpages--;
1094 }
1095 return (count);
1096 }
1097
1098 static int
1099 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1100 {
1101 struct bounce_zone *bz;
1102 int pages;
1103
1104 mtx_assert(&bounce_lock, MA_OWNED);
1105 bz = dmat->bounce_zone;
1106 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1107 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1108 return (map->pagesneeded - (map->pagesreserved + pages));
1109 bz->free_bpages -= pages;
1110 bz->reserved_bpages += pages;
1111 map->pagesreserved += pages;
1112 pages = map->pagesneeded - map->pagesreserved;
1113
1114 return (pages);
1115 }
1116
1117 static bus_addr_t
1118 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1119 bus_size_t size)
1120 {
1121 struct bounce_zone *bz;
1122 struct bounce_page *bpage;
1123
1124 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1125 KASSERT(map != NULL && map != &nobounce_dmamap,
1126 ("add_bounce_page: bad map %p", map));
1127
1128 bz = dmat->bounce_zone;
1129 if (map->pagesneeded == 0)
1130 panic("add_bounce_page: map doesn't need any pages");
1131 map->pagesneeded--;
1132
1133 if (map->pagesreserved == 0)
1134 panic("add_bounce_page: map doesn't need any pages");
1135 map->pagesreserved--;
1136
1137 mtx_lock(&bounce_lock);
1138 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1139 if (bpage == NULL)
1140 panic("add_bounce_page: free page list is empty");
1141
1142 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1143 bz->reserved_bpages--;
1144 bz->active_bpages++;
1145 mtx_unlock(&bounce_lock);
1146
1147 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1148 /* Page offset needs to be preserved. */
1149 bpage->vaddr |= vaddr & PAGE_MASK;
1150 bpage->busaddr |= vaddr & PAGE_MASK;
1151 }
1152 bpage->datavaddr = vaddr;
1153 bpage->datacount = size;
1154 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1155 return (bpage->busaddr);
1156 }
1157
1158 static void
1159 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1160 {
1161 struct bus_dmamap *map;
1162 struct bounce_zone *bz;
1163
1164 bz = dmat->bounce_zone;
1165 bpage->datavaddr = 0;
1166 bpage->datacount = 0;
1167 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1168 /*
1169 * Reset the bounce page to start at offset 0. Other uses
1170 * of this bounce page may need to store a full page of
1171 * data and/or assume it starts on a page boundary.
1172 */
1173 bpage->vaddr &= ~PAGE_MASK;
1174 bpage->busaddr &= ~PAGE_MASK;
1175 }
1176
1177 mtx_lock(&bounce_lock);
1178 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1179 bz->free_bpages++;
1180 bz->active_bpages--;
1181 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1182 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1183 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1184 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1185 map, links);
1186 busdma_swi_pending = 1;
1187 bz->total_deferred++;
1188 swi_sched(vm_ih, 0);
1189 }
1190 }
1191 mtx_unlock(&bounce_lock);
1192 }
1193
1194 void
1195 busdma_swi(void)
1196 {
1197 bus_dma_tag_t dmat;
1198 struct bus_dmamap *map;
1199
1200 mtx_lock(&bounce_lock);
1201 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1202 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1203 mtx_unlock(&bounce_lock);
1204 dmat = map->dmat;
1205 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1206 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1207 map->callback, map->callback_arg, /*flags*/0);
1208 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1209 mtx_lock(&bounce_lock);
1210 }
1211 mtx_unlock(&bounce_lock);
1212 }
Cache object: a9ae68272f2acea3ec188b8ad1ac3caf
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