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("$FreeBSD$");
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 bus_size_t alignment;
97 bus_size_t boundary;
98 bus_addr_t lowaddr;
99 char zoneid[8];
100 char lowaddrid[20];
101 struct sysctl_ctx_list sysctl_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) +
243 (PAGE_SIZE - 1);
244 newtag->filter = filter;
245 newtag->filterarg = filterarg;
246 newtag->maxsize = maxsize;
247 newtag->nsegments = nsegments;
248 newtag->maxsegsz = maxsegsz;
249 newtag->flags = flags;
250 newtag->ref_count = 1; /* Count ourself */
251 newtag->map_count = 0;
252 if (lockfunc != NULL) {
253 newtag->lockfunc = lockfunc;
254 newtag->lockfuncarg = lockfuncarg;
255 } else {
256 newtag->lockfunc = dflt_lock;
257 newtag->lockfuncarg = NULL;
258 }
259 newtag->segments = NULL;
260
261 /* Take into account any restrictions imposed by our parent tag */
262 if (parent != NULL) {
263 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
264 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
265 if (newtag->boundary == 0)
266 newtag->boundary = parent->boundary;
267 else if (parent->boundary != 0)
268 newtag->boundary = MIN(parent->boundary,
269 newtag->boundary);
270 if (newtag->filter == NULL) {
271 /*
272 * Short circuit looking at our parent directly
273 * since we have encapsulated all of its information
274 */
275 newtag->filter = parent->filter;
276 newtag->filterarg = parent->filterarg;
277 newtag->parent = parent->parent;
278 }
279 if (newtag->parent != NULL)
280 atomic_add_int(&parent->ref_count, 1);
281 }
282
283 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
284 || newtag->alignment > 1)
285 newtag->flags |= BUS_DMA_COULD_BOUNCE;
286
287 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
288 (flags & BUS_DMA_ALLOCNOW) != 0) {
289 struct bounce_zone *bz;
290
291 /* Must bounce */
292
293 if ((error = alloc_bounce_zone(newtag)) != 0) {
294 free(newtag, M_DEVBUF);
295 return (error);
296 }
297 bz = newtag->bounce_zone;
298
299 if (ptoa(bz->total_bpages) < maxsize) {
300 int pages;
301
302 pages = atop(maxsize) - bz->total_bpages;
303
304 /* Add pages to our bounce pool */
305 if (alloc_bounce_pages(newtag, pages) < pages)
306 error = ENOMEM;
307 }
308 /* Performed initial allocation */
309 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
310 }
311
312 if (error != 0) {
313 free(newtag, M_DEVBUF);
314 } else {
315 *dmat = newtag;
316 }
317 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
318 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
319 return (error);
320 }
321
322 int
323 bus_dma_tag_destroy(bus_dma_tag_t dmat)
324 {
325 bus_dma_tag_t dmat_copy;
326 int error;
327
328 error = 0;
329 dmat_copy = dmat;
330
331 if (dmat != NULL) {
332
333 if (dmat->map_count != 0) {
334 error = EBUSY;
335 goto out;
336 }
337
338 while (dmat != NULL) {
339 bus_dma_tag_t parent;
340
341 parent = dmat->parent;
342 atomic_subtract_int(&dmat->ref_count, 1);
343 if (dmat->ref_count == 0) {
344 if (dmat->segments != NULL)
345 free(dmat->segments, M_DEVBUF);
346 free(dmat, M_DEVBUF);
347 /*
348 * Last reference count, so
349 * release our reference
350 * count on our parent.
351 */
352 dmat = parent;
353 } else
354 dmat = NULL;
355 }
356 }
357 out:
358 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
359 return (error);
360 }
361
362 /*
363 * Allocate a handle for mapping from kva/uva/physical
364 * address space into bus device space.
365 */
366 int
367 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
368 {
369 int error;
370
371 error = 0;
372
373 if (dmat->segments == NULL) {
374 dmat->segments = (bus_dma_segment_t *)malloc(
375 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
376 M_NOWAIT);
377 if (dmat->segments == NULL) {
378 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
379 __func__, dmat, ENOMEM);
380 return (ENOMEM);
381 }
382 }
383
384 /*
385 * Bouncing might be required if the driver asks for an active
386 * exclusion region, a data alignment that is stricter than 1, and/or
387 * an active address boundary.
388 */
389 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
390
391 /* Must bounce */
392 struct bounce_zone *bz;
393 int maxpages;
394
395 if (dmat->bounce_zone == NULL) {
396 if ((error = alloc_bounce_zone(dmat)) != 0)
397 return (error);
398 }
399 bz = dmat->bounce_zone;
400
401 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
402 M_NOWAIT | M_ZERO);
403 if (*mapp == NULL) {
404 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
405 __func__, dmat, ENOMEM);
406 return (ENOMEM);
407 }
408
409 /* Initialize the new map */
410 STAILQ_INIT(&((*mapp)->bpages));
411
412 /*
413 * Attempt to add pages to our pool on a per-instance
414 * basis up to a sane limit.
415 */
416 if (dmat->alignment > 1)
417 maxpages = MAX_BPAGES;
418 else
419 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
420 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
421 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
422 int pages;
423
424 pages = MAX(atop(dmat->maxsize), 1);
425 pages = MIN(maxpages - bz->total_bpages, pages);
426 pages = MAX(pages, 1);
427 if (alloc_bounce_pages(dmat, pages) < pages)
428 error = ENOMEM;
429
430 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
431 if (error == 0)
432 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
433 } else {
434 error = 0;
435 }
436 }
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 free(map, M_DEVBUF);
461 }
462 dmat->map_count--;
463 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
464 return (0);
465 }
466
467
468 /*
469 * Allocate a piece of memory that can be efficiently mapped into
470 * bus device space based on the constraints lited in the dma tag.
471 * A dmamap to for use with dmamap_load is also allocated.
472 */
473 int
474 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
475 bus_dmamap_t *mapp)
476 {
477 int mflags;
478
479 if (flags & BUS_DMA_NOWAIT)
480 mflags = M_NOWAIT;
481 else
482 mflags = M_WAITOK;
483 if (flags & BUS_DMA_ZERO)
484 mflags |= M_ZERO;
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 M_NOWAIT);
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
500 /*
501 * XXX:
502 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
503 * alignment guarantees of malloc need to be nailed down, and the
504 * code below should be rewritten to take that into account.
505 *
506 * In the meantime, we'll warn the user if malloc gets it wrong.
507 */
508 if ((dmat->maxsize <= PAGE_SIZE) &&
509 (dmat->alignment < dmat->maxsize) &&
510 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
511 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
512 } else {
513 /*
514 * XXX Use Contigmalloc until it is merged into this facility
515 * and handles multi-seg allocations. Nobody is doing
516 * multi-seg allocations yet though.
517 * XXX Certain AGP hardware does.
518 */
519 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
520 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
521 dmat->boundary);
522 }
523 if (*vaddr == NULL) {
524 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
525 __func__, dmat, dmat->flags, ENOMEM);
526 return (ENOMEM);
527 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
528 printf("bus_dmamem_alloc failed to align memory properly.\n");
529 }
530 if (flags & BUS_DMA_NOCACHE)
531 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
532 PAT_UNCACHEABLE);
533 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
534 __func__, dmat, dmat->flags, ENOMEM);
535 return (0);
536 }
537
538 /*
539 * Free a piece of memory and it's allociated dmamap, that was allocated
540 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
541 */
542 void
543 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
544 {
545 /*
546 * dmamem does not need to be bounced, so the map should be
547 * NULL
548 */
549 if (map != NULL)
550 panic("bus_dmamem_free: Invalid map freed\n");
551 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
552 if ((dmat->maxsize <= PAGE_SIZE) &&
553 (dmat->alignment < dmat->maxsize) &&
554 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
555 free(vaddr, M_DEVBUF);
556 else {
557 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
558 }
559 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
560 }
561
562 /*
563 * Utility function to load a linear buffer. lastaddrp holds state
564 * between invocations (for multiple-buffer loads). segp contains
565 * the starting segment on entrace, and the ending segment on exit.
566 * first indicates if this is the first invocation of this function.
567 */
568 static __inline int
569 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
570 bus_dmamap_t map,
571 void *buf, bus_size_t buflen,
572 pmap_t pmap,
573 int flags,
574 bus_addr_t *lastaddrp,
575 bus_dma_segment_t *segs,
576 int *segp,
577 int first)
578 {
579 bus_size_t sgsize;
580 bus_addr_t curaddr, lastaddr, baddr, bmask;
581 vm_offset_t vaddr;
582 bus_addr_t paddr;
583 int needbounce = 0;
584 int seg;
585
586 if (map == NULL)
587 map = &nobounce_dmamap;
588
589 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
590 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
591 vm_offset_t vendaddr;
592
593 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
594 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
595 dmat->boundary, dmat->alignment);
596 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
597 map, &nobounce_dmamap, map->pagesneeded);
598 /*
599 * Count the number of bounce pages
600 * needed in order to complete this transfer
601 */
602 vaddr = trunc_page((vm_offset_t)buf);
603 vendaddr = (vm_offset_t)buf + buflen;
604
605 while (vaddr < vendaddr) {
606 paddr = pmap_kextract(vaddr);
607 if (run_filter(dmat, paddr) != 0) {
608 needbounce = 1;
609 map->pagesneeded++;
610 }
611 vaddr += PAGE_SIZE;
612 }
613 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
614 }
615
616 /* Reserve Necessary Bounce Pages */
617 if (map->pagesneeded != 0) {
618 mtx_lock(&bounce_lock);
619 if (flags & BUS_DMA_NOWAIT) {
620 if (reserve_bounce_pages(dmat, map, 0) != 0) {
621 mtx_unlock(&bounce_lock);
622 return (ENOMEM);
623 }
624 } else {
625 if (reserve_bounce_pages(dmat, map, 1) != 0) {
626 /* Queue us for resources */
627 map->dmat = dmat;
628 map->buf = buf;
629 map->buflen = buflen;
630 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
631 map, links);
632 mtx_unlock(&bounce_lock);
633 return (EINPROGRESS);
634 }
635 }
636 mtx_unlock(&bounce_lock);
637 }
638
639 vaddr = (vm_offset_t)buf;
640 lastaddr = *lastaddrp;
641 bmask = ~(dmat->boundary - 1);
642
643 for (seg = *segp; buflen > 0 ; ) {
644 /*
645 * Get the physical address for this segment.
646 */
647 if (pmap)
648 curaddr = pmap_extract(pmap, vaddr);
649 else
650 curaddr = pmap_kextract(vaddr);
651
652 /*
653 * Compute the segment size, and adjust counts.
654 */
655 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
656 if (sgsize > dmat->maxsegsz)
657 sgsize = dmat->maxsegsz;
658 if (buflen < sgsize)
659 sgsize = buflen;
660
661 /*
662 * Make sure we don't cross any boundaries.
663 */
664 if (dmat->boundary > 0) {
665 baddr = (curaddr + dmat->boundary) & bmask;
666 if (sgsize > (baddr - curaddr))
667 sgsize = (baddr - curaddr);
668 }
669
670 if (map->pagesneeded != 0 && run_filter(dmat, curaddr))
671 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
672
673 /*
674 * Insert chunk into a segment, coalescing with
675 * previous segment if possible.
676 */
677 if (first) {
678 segs[seg].ds_addr = curaddr;
679 segs[seg].ds_len = sgsize;
680 first = 0;
681 } else {
682 if (needbounce == 0 && curaddr == lastaddr &&
683 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
684 (dmat->boundary == 0 ||
685 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
686 segs[seg].ds_len += sgsize;
687 else {
688 if (++seg >= dmat->nsegments)
689 break;
690 segs[seg].ds_addr = curaddr;
691 segs[seg].ds_len = sgsize;
692 }
693 }
694
695 lastaddr = curaddr + sgsize;
696 vaddr += sgsize;
697 buflen -= sgsize;
698 }
699
700 *segp = seg;
701 *lastaddrp = lastaddr;
702
703 /*
704 * Did we fit?
705 */
706 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
707 }
708
709 /*
710 * Map the buffer buf into bus space using the dmamap map.
711 */
712 int
713 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
714 bus_size_t buflen, bus_dmamap_callback_t *callback,
715 void *callback_arg, int flags)
716 {
717 bus_addr_t lastaddr = 0;
718 int error, nsegs = 0;
719
720 if (map != NULL) {
721 flags |= BUS_DMA_WAITOK;
722 map->callback = callback;
723 map->callback_arg = callback_arg;
724 }
725
726 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
727 &lastaddr, dmat->segments, &nsegs, 1);
728
729 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
730 __func__, dmat, dmat->flags, error, nsegs + 1);
731
732 if (error == EINPROGRESS) {
733 return (error);
734 }
735
736 if (error)
737 (*callback)(callback_arg, dmat->segments, 0, error);
738 else
739 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
740
741 /*
742 * Return ENOMEM to the caller so that it can pass it up the stack.
743 * This error only happens when NOWAIT is set, so deferal is disabled.
744 */
745 if (error == ENOMEM)
746 return (error);
747
748 return (0);
749 }
750
751
752 /*
753 * Like _bus_dmamap_load(), but for mbufs.
754 */
755 int
756 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
757 struct mbuf *m0,
758 bus_dmamap_callback2_t *callback, void *callback_arg,
759 int flags)
760 {
761 int nsegs, error;
762
763 M_ASSERTPKTHDR(m0);
764
765 flags |= BUS_DMA_NOWAIT;
766 nsegs = 0;
767 error = 0;
768 if (m0->m_pkthdr.len <= dmat->maxsize) {
769 int first = 1;
770 bus_addr_t lastaddr = 0;
771 struct mbuf *m;
772
773 for (m = m0; m != NULL && error == 0; m = m->m_next) {
774 if (m->m_len > 0) {
775 error = _bus_dmamap_load_buffer(dmat, map,
776 m->m_data, m->m_len,
777 NULL, flags, &lastaddr,
778 dmat->segments, &nsegs, first);
779 first = 0;
780 }
781 }
782 } else {
783 error = EINVAL;
784 }
785
786 if (error) {
787 /* force "no valid mappings" in callback */
788 (*callback)(callback_arg, dmat->segments, 0, 0, error);
789 } else {
790 (*callback)(callback_arg, dmat->segments,
791 nsegs+1, m0->m_pkthdr.len, error);
792 }
793 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
794 __func__, dmat, dmat->flags, error, nsegs + 1);
795 return (error);
796 }
797
798 int
799 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
800 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
801 int flags)
802 {
803 int error;
804
805 M_ASSERTPKTHDR(m0);
806
807 flags |= BUS_DMA_NOWAIT;
808 *nsegs = 0;
809 error = 0;
810 if (m0->m_pkthdr.len <= dmat->maxsize) {
811 int first = 1;
812 bus_addr_t lastaddr = 0;
813 struct mbuf *m;
814
815 for (m = m0; m != NULL && error == 0; m = m->m_next) {
816 if (m->m_len > 0) {
817 error = _bus_dmamap_load_buffer(dmat, map,
818 m->m_data, m->m_len,
819 NULL, flags, &lastaddr,
820 segs, nsegs, first);
821 first = 0;
822 }
823 }
824 } else {
825 error = EINVAL;
826 }
827
828 /* XXX FIXME: Having to increment nsegs is really annoying */
829 ++*nsegs;
830 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
831 __func__, dmat, dmat->flags, error, *nsegs);
832 return (error);
833 }
834
835 /*
836 * Like _bus_dmamap_load(), but for uios.
837 */
838 int
839 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
840 struct uio *uio,
841 bus_dmamap_callback2_t *callback, void *callback_arg,
842 int flags)
843 {
844 bus_addr_t lastaddr = 0;
845 int nsegs, error, first, i;
846 bus_size_t resid;
847 struct iovec *iov;
848 pmap_t pmap;
849
850 flags |= BUS_DMA_NOWAIT;
851 resid = uio->uio_resid;
852 iov = uio->uio_iov;
853
854 if (uio->uio_segflg == UIO_USERSPACE) {
855 KASSERT(uio->uio_td != NULL,
856 ("bus_dmamap_load_uio: USERSPACE but no proc"));
857 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
858 } else
859 pmap = NULL;
860
861 nsegs = 0;
862 error = 0;
863 first = 1;
864 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
865 /*
866 * Now at the first iovec to load. Load each iovec
867 * until we have exhausted the residual count.
868 */
869 bus_size_t minlen =
870 resid < iov[i].iov_len ? resid : iov[i].iov_len;
871 caddr_t addr = (caddr_t) iov[i].iov_base;
872
873 if (minlen > 0) {
874 error = _bus_dmamap_load_buffer(dmat, map,
875 addr, minlen, pmap, flags, &lastaddr,
876 dmat->segments, &nsegs, first);
877 first = 0;
878
879 resid -= minlen;
880 }
881 }
882
883 if (error) {
884 /* force "no valid mappings" in callback */
885 (*callback)(callback_arg, dmat->segments, 0, 0, error);
886 } else {
887 (*callback)(callback_arg, dmat->segments,
888 nsegs+1, uio->uio_resid, error);
889 }
890 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
891 __func__, dmat, dmat->flags, error, nsegs + 1);
892 return (error);
893 }
894
895 /*
896 * Release the mapping held by map.
897 */
898 void
899 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
900 {
901 struct bounce_page *bpage;
902
903 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
904 STAILQ_REMOVE_HEAD(&map->bpages, links);
905 free_bounce_page(dmat, bpage);
906 }
907 }
908
909 void
910 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
911 {
912 struct bounce_page *bpage;
913
914 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
915 /*
916 * Handle data bouncing. We might also
917 * want to add support for invalidating
918 * the caches on broken hardware
919 */
920 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
921 "performing bounce", __func__, op, dmat, dmat->flags);
922
923 if (op & BUS_DMASYNC_PREWRITE) {
924 while (bpage != NULL) {
925 bcopy((void *)bpage->datavaddr,
926 (void *)bpage->vaddr,
927 bpage->datacount);
928 bpage = STAILQ_NEXT(bpage, links);
929 }
930 dmat->bounce_zone->total_bounced++;
931 }
932
933 if (op & BUS_DMASYNC_POSTREAD) {
934 while (bpage != NULL) {
935 bcopy((void *)bpage->vaddr,
936 (void *)bpage->datavaddr,
937 bpage->datacount);
938 bpage = STAILQ_NEXT(bpage, links);
939 }
940 dmat->bounce_zone->total_bounced++;
941 }
942 }
943 }
944
945 static void
946 init_bounce_pages(void *dummy __unused)
947 {
948
949 total_bpages = 0;
950 STAILQ_INIT(&bounce_zone_list);
951 STAILQ_INIT(&bounce_map_waitinglist);
952 STAILQ_INIT(&bounce_map_callbacklist);
953 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
954 }
955 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
956
957 static struct sysctl_ctx_list *
958 busdma_sysctl_tree(struct bounce_zone *bz)
959 {
960 return (&bz->sysctl_tree);
961 }
962
963 static struct sysctl_oid *
964 busdma_sysctl_tree_top(struct bounce_zone *bz)
965 {
966 return (bz->sysctl_tree_top);
967 }
968
969 static int
970 alloc_bounce_zone(bus_dma_tag_t dmat)
971 {
972 struct bounce_zone *bz;
973
974 /* Check to see if we already have a suitable zone */
975 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
976 if ((dmat->alignment <= bz->alignment)
977 && (dmat->boundary <= bz->boundary)
978 && (dmat->lowaddr >= bz->lowaddr)) {
979 dmat->bounce_zone = bz;
980 return (0);
981 }
982 }
983
984 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
985 M_NOWAIT | M_ZERO)) == NULL)
986 return (ENOMEM);
987
988 STAILQ_INIT(&bz->bounce_page_list);
989 bz->free_bpages = 0;
990 bz->reserved_bpages = 0;
991 bz->active_bpages = 0;
992 bz->lowaddr = dmat->lowaddr;
993 bz->alignment = dmat->alignment;
994 bz->boundary = dmat->boundary;
995 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
996 busdma_zonecount++;
997 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
998 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
999 dmat->bounce_zone = bz;
1000
1001 sysctl_ctx_init(&bz->sysctl_tree);
1002 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1003 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1004 CTLFLAG_RD, 0, "");
1005 if (bz->sysctl_tree_top == NULL) {
1006 sysctl_ctx_free(&bz->sysctl_tree);
1007 return (0); /* XXX error code? */
1008 }
1009
1010 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1011 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1012 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1013 "Total bounce pages");
1014 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1016 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1017 "Free bounce pages");
1018 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1019 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1020 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1021 "Reserved bounce pages");
1022 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1023 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1024 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1025 "Active bounce pages");
1026 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1027 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1028 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1029 "Total bounce requests");
1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1032 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1033 "Total bounce requests that were deferred");
1034 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1035 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1036 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1037 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1038 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1039 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1040 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1041 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1042 "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
1043
1044 return (0);
1045 }
1046
1047 static int
1048 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1049 {
1050 struct bounce_zone *bz;
1051 int count;
1052
1053 bz = dmat->bounce_zone;
1054 count = 0;
1055 while (numpages > 0) {
1056 struct bounce_page *bpage;
1057
1058 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1059 M_NOWAIT | M_ZERO);
1060
1061 if (bpage == NULL)
1062 break;
1063 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1064 M_NOWAIT, 0ul,
1065 bz->lowaddr,
1066 PAGE_SIZE,
1067 bz->boundary);
1068 if (bpage->vaddr == 0) {
1069 free(bpage, M_DEVBUF);
1070 break;
1071 }
1072 bpage->busaddr = pmap_kextract(bpage->vaddr);
1073 mtx_lock(&bounce_lock);
1074 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1075 total_bpages++;
1076 bz->total_bpages++;
1077 bz->free_bpages++;
1078 mtx_unlock(&bounce_lock);
1079 count++;
1080 numpages--;
1081 }
1082 return (count);
1083 }
1084
1085 static int
1086 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1087 {
1088 struct bounce_zone *bz;
1089 int pages;
1090
1091 mtx_assert(&bounce_lock, MA_OWNED);
1092 bz = dmat->bounce_zone;
1093 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1094 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1095 return (map->pagesneeded - (map->pagesreserved + pages));
1096 bz->free_bpages -= pages;
1097 bz->reserved_bpages += pages;
1098 map->pagesreserved += pages;
1099 pages = map->pagesneeded - map->pagesreserved;
1100
1101 return (pages);
1102 }
1103
1104 static bus_addr_t
1105 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1106 bus_size_t size)
1107 {
1108 struct bounce_zone *bz;
1109 struct bounce_page *bpage;
1110
1111 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1112 KASSERT(map != NULL && map != &nobounce_dmamap,
1113 ("add_bounce_page: bad map %p", map));
1114
1115 bz = dmat->bounce_zone;
1116 if (map->pagesneeded == 0)
1117 panic("add_bounce_page: map doesn't need any pages");
1118 map->pagesneeded--;
1119
1120 if (map->pagesreserved == 0)
1121 panic("add_bounce_page: map doesn't need any pages");
1122 map->pagesreserved--;
1123
1124 mtx_lock(&bounce_lock);
1125 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1126 if (bpage == NULL)
1127 panic("add_bounce_page: free page list is empty");
1128
1129 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1130 bz->reserved_bpages--;
1131 bz->active_bpages++;
1132 mtx_unlock(&bounce_lock);
1133
1134 bpage->datavaddr = vaddr;
1135 bpage->datacount = size;
1136 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1137 return (bpage->busaddr);
1138 }
1139
1140 static void
1141 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1142 {
1143 struct bus_dmamap *map;
1144 struct bounce_zone *bz;
1145
1146 bz = dmat->bounce_zone;
1147 bpage->datavaddr = 0;
1148 bpage->datacount = 0;
1149
1150 mtx_lock(&bounce_lock);
1151 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1152 bz->free_bpages++;
1153 bz->active_bpages--;
1154 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1155 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1156 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1157 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1158 map, links);
1159 busdma_swi_pending = 1;
1160 bz->total_deferred++;
1161 swi_sched(vm_ih, 0);
1162 }
1163 }
1164 mtx_unlock(&bounce_lock);
1165 }
1166
1167 void
1168 busdma_swi(void)
1169 {
1170 bus_dma_tag_t dmat;
1171 struct bus_dmamap *map;
1172
1173 mtx_lock(&bounce_lock);
1174 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1175 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1176 mtx_unlock(&bounce_lock);
1177 dmat = map->dmat;
1178 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1179 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1180 map->callback, map->callback_arg, /*flags*/0);
1181 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1182 mtx_lock(&bounce_lock);
1183 }
1184 mtx_unlock(&bounce_lock);
1185 }
Cache object: 4e39e6c843cbe16dde8db1c227e86ad3
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