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/kdb.h>
32 #include <ddb/ddb.h>
33 #include <ddb/db_output.h>
34 #include <sys/systm.h>
35 #include <sys/malloc.h>
36 #include <sys/bus.h>
37 #include <sys/interrupt.h>
38 #include <sys/kernel.h>
39 #include <sys/ktr.h>
40 #include <sys/lock.h>
41 #include <sys/proc.h>
42 #include <sys/mutex.h>
43 #include <sys/mbuf.h>
44 #include <sys/uio.h>
45 #include <sys/sysctl.h>
46
47 #include <vm/vm.h>
48 #include <vm/vm_page.h>
49 #include <vm/vm_map.h>
50
51 #include <machine/atomic.h>
52 #include <machine/bus.h>
53 #include <machine/md_var.h>
54 #include <machine/specialreg.h>
55
56 #define MAX_BPAGES 512
57 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
58 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
59
60 struct bounce_zone;
61
62 struct bus_dma_tag {
63 bus_dma_tag_t parent;
64 bus_size_t alignment;
65 bus_size_t boundary;
66 bus_addr_t lowaddr;
67 bus_addr_t highaddr;
68 bus_dma_filter_t *filter;
69 void *filterarg;
70 bus_size_t maxsize;
71 u_int nsegments;
72 bus_size_t maxsegsz;
73 int flags;
74 int ref_count;
75 int map_count;
76 bus_dma_lock_t *lockfunc;
77 void *lockfuncarg;
78 bus_dma_segment_t *segments;
79 struct bounce_zone *bounce_zone;
80 };
81
82 struct bounce_page {
83 vm_offset_t vaddr; /* kva of bounce buffer */
84 bus_addr_t busaddr; /* Physical address */
85 vm_offset_t datavaddr; /* kva of client data */
86 bus_size_t datacount; /* client data count */
87 STAILQ_ENTRY(bounce_page) links;
88 };
89
90 int busdma_swi_pending;
91
92 struct bounce_zone {
93 STAILQ_ENTRY(bounce_zone) links;
94 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
95 int total_bpages;
96 int free_bpages;
97 int reserved_bpages;
98 int active_bpages;
99 int total_bounced;
100 int total_deferred;
101 bus_size_t alignment;
102 bus_size_t boundary;
103 bus_addr_t lowaddr;
104 char zoneid[8];
105 char lowaddrid[20];
106 struct sysctl_ctx_list sysctl_tree;
107 struct sysctl_oid *sysctl_tree_top;
108 };
109
110 static struct mtx bounce_lock;
111 static int total_bpages;
112 static int busdma_zonecount;
113 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
114
115 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
116 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
117 "Total bounce pages");
118
119 struct bus_dmamap {
120 struct bp_list bpages;
121 int pagesneeded;
122 int pagesreserved;
123 bus_dma_tag_t dmat;
124 void *buf; /* unmapped buffer pointer */
125 bus_size_t buflen; /* unmapped buffer length */
126 bus_dmamap_callback_t *callback;
127 void *callback_arg;
128 STAILQ_ENTRY(bus_dmamap) links;
129 };
130
131 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
132 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
133 static struct bus_dmamap nobounce_dmamap;
134
135 static void init_bounce_pages(void *dummy);
136 static int alloc_bounce_zone(bus_dma_tag_t dmat);
137 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
138 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
139 int commit);
140 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
141 vm_offset_t vaddr, bus_size_t size);
142 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
143 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
144 int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
145 bus_size_t buflen, int flags, int *nb);
146
147 /*
148 * Return true if a match is made.
149 *
150 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
151 *
152 * If paddr is within the bounds of the dma tag then call the filter callback
153 * to check for a match, if there is no filter callback then assume a match.
154 */
155 int
156 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
157 {
158 int retval;
159
160 retval = 0;
161
162 do {
163 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
164 || ((paddr & (dmat->alignment - 1)) != 0))
165 && (dmat->filter == NULL
166 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
167 retval = 1;
168
169 dmat = dmat->parent;
170 } while (retval == 0 && dmat != NULL);
171 return (retval);
172 }
173
174 /*
175 * Convenience function for manipulating driver locks from busdma (during
176 * busdma_swi, for example). Drivers that don't provide their own locks
177 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
178 * non-mutex locking scheme don't have to use this at all.
179 */
180 void
181 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
182 {
183 struct mtx *dmtx;
184
185 dmtx = (struct mtx *)arg;
186 switch (op) {
187 case BUS_DMA_LOCK:
188 mtx_lock(dmtx);
189 break;
190 case BUS_DMA_UNLOCK:
191 mtx_unlock(dmtx);
192 break;
193 default:
194 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
195 }
196 }
197
198 /*
199 * dflt_lock should never get called. It gets put into the dma tag when
200 * lockfunc == NULL, which is only valid if the maps that are associated
201 * with the tag are meant to never be defered.
202 * XXX Should have a way to identify which driver is responsible here.
203 */
204 static void
205 dflt_lock(void *arg, bus_dma_lock_op_t op)
206 {
207 panic("driver error: busdma dflt_lock called");
208 }
209
210 /*
211 * Allocate a device specific dma_tag.
212 */
213 int
214 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
215 bus_size_t boundary, bus_addr_t lowaddr,
216 bus_addr_t highaddr, bus_dma_filter_t *filter,
217 void *filterarg, bus_size_t maxsize, int nsegments,
218 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
219 void *lockfuncarg, bus_dma_tag_t *dmat)
220 {
221 bus_dma_tag_t newtag;
222 int error = 0;
223
224 /* Basic sanity checking */
225 if (boundary != 0 && boundary < maxsegsz)
226 maxsegsz = boundary;
227
228 if (maxsegsz == 0) {
229 return (EINVAL);
230 }
231
232 /* Return a NULL tag on failure */
233 *dmat = NULL;
234
235 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
236 M_ZERO | M_NOWAIT);
237 if (newtag == NULL) {
238 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
239 __func__, newtag, 0, error);
240 return (ENOMEM);
241 }
242
243 newtag->parent = parent;
244 newtag->alignment = alignment;
245 newtag->boundary = boundary;
246 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
247 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) +
248 (PAGE_SIZE - 1);
249 newtag->filter = filter;
250 newtag->filterarg = filterarg;
251 newtag->maxsize = maxsize;
252 newtag->nsegments = nsegments;
253 newtag->maxsegsz = maxsegsz;
254 newtag->flags = flags;
255 newtag->ref_count = 1; /* Count ourself */
256 newtag->map_count = 0;
257 if (lockfunc != NULL) {
258 newtag->lockfunc = lockfunc;
259 newtag->lockfuncarg = lockfuncarg;
260 } else {
261 newtag->lockfunc = dflt_lock;
262 newtag->lockfuncarg = NULL;
263 }
264 newtag->segments = NULL;
265
266 /* Take into account any restrictions imposed by our parent tag */
267 if (parent != NULL) {
268 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
269 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
270 if (newtag->boundary == 0)
271 newtag->boundary = parent->boundary;
272 else if (parent->boundary != 0)
273 newtag->boundary = MIN(parent->boundary,
274 newtag->boundary);
275 if ((newtag->filter != NULL) ||
276 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0))
277 newtag->flags |= BUS_DMA_COULD_BOUNCE;
278 if (newtag->filter == NULL) {
279 /*
280 * Short circuit looking at our parent directly
281 * since we have encapsulated all of its information
282 */
283 newtag->filter = parent->filter;
284 newtag->filterarg = parent->filterarg;
285 newtag->parent = parent->parent;
286 }
287 if (newtag->parent != NULL)
288 atomic_add_int(&parent->ref_count, 1);
289 }
290
291 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
292 || newtag->alignment > 1)
293 newtag->flags |= BUS_DMA_COULD_BOUNCE;
294
295 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
296 (flags & BUS_DMA_ALLOCNOW) != 0) {
297 struct bounce_zone *bz;
298
299 /* Must bounce */
300
301 if ((error = alloc_bounce_zone(newtag)) != 0) {
302 free(newtag, M_DEVBUF);
303 return (error);
304 }
305 bz = newtag->bounce_zone;
306
307 if (ptoa(bz->total_bpages) < maxsize) {
308 int pages;
309
310 pages = atop(maxsize) - bz->total_bpages;
311
312 /* Add pages to our bounce pool */
313 if (alloc_bounce_pages(newtag, pages) < pages)
314 error = ENOMEM;
315 }
316 /* Performed initial allocation */
317 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
318 }
319
320 if (error != 0) {
321 free(newtag, M_DEVBUF);
322 } else {
323 *dmat = newtag;
324 }
325 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
326 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
327 return (error);
328 }
329
330 int
331 bus_dma_tag_destroy(bus_dma_tag_t dmat)
332 {
333 bus_dma_tag_t dmat_copy;
334 int error;
335
336 error = 0;
337 dmat_copy = dmat;
338
339 if (dmat != NULL) {
340
341 if (dmat->map_count != 0) {
342 error = EBUSY;
343 goto out;
344 }
345
346 while (dmat != NULL) {
347 bus_dma_tag_t parent;
348
349 parent = dmat->parent;
350 atomic_subtract_int(&dmat->ref_count, 1);
351 if (dmat->ref_count == 0) {
352 if (dmat->segments != NULL)
353 free(dmat->segments, M_DEVBUF);
354 free(dmat, M_DEVBUF);
355 /*
356 * Last reference count, so
357 * release our reference
358 * count on our parent.
359 */
360 dmat = parent;
361 } else
362 dmat = NULL;
363 }
364 }
365 out:
366 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
367 return (error);
368 }
369
370 /*
371 * Allocate a handle for mapping from kva/uva/physical
372 * address space into bus device space.
373 */
374 int
375 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
376 {
377 int error;
378
379 error = 0;
380
381 if (dmat->segments == NULL) {
382 dmat->segments = (bus_dma_segment_t *)malloc(
383 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
384 M_NOWAIT);
385 if (dmat->segments == NULL) {
386 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
387 __func__, dmat, ENOMEM);
388 return (ENOMEM);
389 }
390 }
391
392 /*
393 * Bouncing might be required if the driver asks for an active
394 * exclusion region, a data alignment that is stricter than 1, and/or
395 * an active address boundary.
396 */
397 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
398
399 /* Must bounce */
400 struct bounce_zone *bz;
401 int maxpages;
402
403 if (dmat->bounce_zone == NULL) {
404 if ((error = alloc_bounce_zone(dmat)) != 0)
405 return (error);
406 }
407 bz = dmat->bounce_zone;
408
409 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
410 M_NOWAIT | M_ZERO);
411 if (*mapp == NULL) {
412 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
413 __func__, dmat, ENOMEM);
414 return (ENOMEM);
415 }
416
417 /* Initialize the new map */
418 STAILQ_INIT(&((*mapp)->bpages));
419
420 /*
421 * Attempt to add pages to our pool on a per-instance
422 * basis up to a sane limit.
423 */
424 if (dmat->alignment > 1)
425 maxpages = MAX_BPAGES;
426 else
427 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
428 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
429 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
430 int pages;
431
432 pages = MAX(atop(dmat->maxsize), 1);
433 pages = MIN(maxpages - bz->total_bpages, pages);
434 pages = MAX(pages, 1);
435 if (alloc_bounce_pages(dmat, pages) < pages)
436 error = ENOMEM;
437
438 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
439 if (error == 0)
440 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
441 } else {
442 error = 0;
443 }
444 }
445 } else {
446 *mapp = NULL;
447 }
448 if (error == 0)
449 dmat->map_count++;
450 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
451 __func__, dmat, dmat->flags, error);
452 return (error);
453 }
454
455 /*
456 * Destroy a handle for mapping from kva/uva/physical
457 * address space into bus device space.
458 */
459 int
460 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
461 {
462 if (map != NULL && map != &nobounce_dmamap) {
463 if (STAILQ_FIRST(&map->bpages) != NULL) {
464 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
465 __func__, dmat, EBUSY);
466 return (EBUSY);
467 }
468 free(map, M_DEVBUF);
469 }
470 dmat->map_count--;
471 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
472 return (0);
473 }
474
475
476 /*
477 * Allocate a piece of memory that can be efficiently mapped into
478 * bus device space based on the constraints lited in the dma tag.
479 * A dmamap to for use with dmamap_load is also allocated.
480 */
481 int
482 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
483 bus_dmamap_t *mapp)
484 {
485 int mflags;
486
487 if (flags & BUS_DMA_NOWAIT)
488 mflags = M_NOWAIT;
489 else
490 mflags = M_WAITOK;
491 if (flags & BUS_DMA_ZERO)
492 mflags |= M_ZERO;
493
494 /* If we succeed, no mapping/bouncing will be required */
495 *mapp = NULL;
496
497 if (dmat->segments == NULL) {
498 dmat->segments = (bus_dma_segment_t *)malloc(
499 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
500 M_NOWAIT);
501 if (dmat->segments == NULL) {
502 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
503 __func__, dmat, dmat->flags, ENOMEM);
504 return (ENOMEM);
505 }
506 }
507
508 /*
509 * XXX:
510 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
511 * alignment guarantees of malloc need to be nailed down, and the
512 * code below should be rewritten to take that into account.
513 *
514 * In the meantime, we'll warn the user if malloc gets it wrong.
515 */
516 if ((dmat->maxsize <= PAGE_SIZE) &&
517 (dmat->alignment < dmat->maxsize) &&
518 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
519 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
520 } else {
521 /*
522 * XXX Use Contigmalloc until it is merged into this facility
523 * and handles multi-seg allocations. Nobody is doing
524 * multi-seg allocations yet though.
525 * XXX Certain AGP hardware does.
526 */
527 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
528 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
529 dmat->boundary);
530 }
531 if (*vaddr == NULL) {
532 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
533 __func__, dmat, dmat->flags, ENOMEM);
534 return (ENOMEM);
535 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
536 printf("bus_dmamem_alloc failed to align memory properly.\n");
537 }
538 if (flags & BUS_DMA_NOCACHE)
539 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
540 PAT_UNCACHEABLE);
541 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
542 __func__, dmat, dmat->flags, ENOMEM);
543 return (0);
544 }
545
546 /*
547 * Free a piece of memory and it's allociated dmamap, that was allocated
548 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
549 */
550 void
551 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
552 {
553 /*
554 * dmamem does not need to be bounced, so the map should be
555 * NULL
556 */
557 if (map != NULL)
558 panic("bus_dmamem_free: Invalid map freed\n");
559 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
560 if ((dmat->maxsize <= PAGE_SIZE) &&
561 (dmat->alignment < dmat->maxsize) &&
562 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
563 free(vaddr, M_DEVBUF);
564 else {
565 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
566 }
567 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
568 }
569
570 int
571 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
572 bus_size_t buflen, int flags, int *nb)
573 {
574 vm_offset_t vaddr;
575 vm_offset_t vendaddr;
576 bus_addr_t paddr;
577 int needbounce = *nb;
578
579 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
580 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
581 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
582 dmat->boundary, dmat->alignment);
583 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
584 map, &nobounce_dmamap, map->pagesneeded);
585 /*
586 * Count the number of bounce pages
587 * needed in order to complete this transfer
588 */
589 vaddr = trunc_page((vm_offset_t)buf);
590 vendaddr = (vm_offset_t)buf + buflen;
591
592 while (vaddr < vendaddr) {
593 paddr = pmap_kextract(vaddr);
594 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
595 run_filter(dmat, paddr) != 0) {
596 needbounce = 1;
597 map->pagesneeded++;
598 }
599 vaddr += PAGE_SIZE;
600 }
601 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
602 }
603
604 /* Reserve Necessary Bounce Pages */
605 if (map->pagesneeded != 0) {
606 mtx_lock(&bounce_lock);
607 if (flags & BUS_DMA_NOWAIT) {
608 if (reserve_bounce_pages(dmat, map, 0) != 0) {
609 mtx_unlock(&bounce_lock);
610 return (ENOMEM);
611 }
612 } else {
613 if (reserve_bounce_pages(dmat, map, 1) != 0) {
614 /* Queue us for resources */
615 map->dmat = dmat;
616 map->buf = buf;
617 map->buflen = buflen;
618 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
619 map, links);
620 mtx_unlock(&bounce_lock);
621 return (EINPROGRESS);
622 }
623 }
624 mtx_unlock(&bounce_lock);
625 }
626
627 *nb = needbounce;
628 return (0);
629 }
630
631 /*
632 * Utility function to load a linear buffer. lastaddrp holds state
633 * between invocations (for multiple-buffer loads). segp contains
634 * the starting segment on entrace, and the ending segment on exit.
635 * first indicates if this is the first invocation of this function.
636 */
637 static __inline int
638 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
639 bus_dmamap_t map,
640 void *buf, bus_size_t buflen,
641 pmap_t pmap,
642 int flags,
643 bus_addr_t *lastaddrp,
644 bus_dma_segment_t *segs,
645 int *segp,
646 int first)
647 {
648 bus_size_t sgsize;
649 bus_addr_t curaddr, lastaddr, baddr, bmask;
650 vm_offset_t vaddr;
651 int needbounce = 0;
652 int seg, error;
653
654 if (map == NULL)
655 map = &nobounce_dmamap;
656
657 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
658 error = _bus_dmamap_count_pages(dmat, map, buf, buflen, flags,
659 &needbounce);
660 if (error)
661 return (error);
662 }
663
664 vaddr = (vm_offset_t)buf;
665 lastaddr = *lastaddrp;
666 bmask = ~(dmat->boundary - 1);
667
668 for (seg = *segp; buflen > 0 ; ) {
669 /*
670 * Get the physical address for this segment.
671 */
672 if (pmap)
673 curaddr = pmap_extract(pmap, vaddr);
674 else
675 curaddr = pmap_kextract(vaddr);
676
677 /*
678 * Compute the segment size, and adjust counts.
679 */
680 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
681 if (sgsize > dmat->maxsegsz)
682 sgsize = dmat->maxsegsz;
683 if (buflen < sgsize)
684 sgsize = buflen;
685
686 /*
687 * Make sure we don't cross any boundaries.
688 */
689 if (dmat->boundary > 0) {
690 baddr = (curaddr + dmat->boundary) & bmask;
691 if (sgsize > (baddr - curaddr))
692 sgsize = (baddr - curaddr);
693 }
694
695 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
696 map->pagesneeded != 0 && run_filter(dmat, curaddr))
697 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
698
699 /*
700 * Insert chunk into a segment, coalescing with
701 * previous segment if possible.
702 */
703 if (first) {
704 segs[seg].ds_addr = curaddr;
705 segs[seg].ds_len = sgsize;
706 first = 0;
707 } else {
708 if (needbounce == 0 && curaddr == lastaddr &&
709 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
710 (dmat->boundary == 0 ||
711 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
712 segs[seg].ds_len += sgsize;
713 else {
714 if (++seg >= dmat->nsegments)
715 break;
716 segs[seg].ds_addr = curaddr;
717 segs[seg].ds_len = sgsize;
718 }
719 }
720
721 lastaddr = curaddr + sgsize;
722 vaddr += sgsize;
723 buflen -= sgsize;
724 }
725
726 *segp = seg;
727 *lastaddrp = lastaddr;
728
729 /*
730 * Did we fit?
731 */
732 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
733 }
734
735 /*
736 * Map the buffer buf into bus space using the dmamap map.
737 */
738 int
739 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
740 bus_size_t buflen, bus_dmamap_callback_t *callback,
741 void *callback_arg, int flags)
742 {
743 bus_addr_t lastaddr = 0;
744 int error, nsegs = 0;
745
746 if (map != NULL) {
747 flags |= BUS_DMA_WAITOK;
748 map->callback = callback;
749 map->callback_arg = callback_arg;
750 }
751
752 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
753 &lastaddr, dmat->segments, &nsegs, 1);
754
755 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
756 __func__, dmat, dmat->flags, error, nsegs + 1);
757
758 if (error == EINPROGRESS) {
759 return (error);
760 }
761
762 if (error)
763 (*callback)(callback_arg, dmat->segments, 0, error);
764 else
765 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
766
767 /*
768 * Return ENOMEM to the caller so that it can pass it up the stack.
769 * This error only happens when NOWAIT is set, so deferal is disabled.
770 */
771 if (error == ENOMEM)
772 return (error);
773
774 return (0);
775 }
776
777
778 /*
779 * Like _bus_dmamap_load(), but for mbufs.
780 */
781 static __inline int
782 _bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
783 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
784 int flags)
785 {
786 int error;
787
788 M_ASSERTPKTHDR(m0);
789
790 flags |= BUS_DMA_NOWAIT;
791 *nsegs = 0;
792 error = 0;
793 if (m0->m_pkthdr.len <= dmat->maxsize) {
794 int first = 1;
795 bus_addr_t lastaddr = 0;
796 struct mbuf *m;
797
798 for (m = m0; m != NULL && error == 0; m = m->m_next) {
799 if (m->m_len > 0) {
800 error = _bus_dmamap_load_buffer(dmat, map,
801 m->m_data, m->m_len,
802 NULL, flags, &lastaddr,
803 segs, nsegs, first);
804 first = 0;
805 }
806 }
807 } else {
808 error = EINVAL;
809 }
810
811 /* XXX FIXME: Having to increment nsegs is really annoying */
812 ++*nsegs;
813 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
814 __func__, dmat, dmat->flags, error, *nsegs);
815 return (error);
816 }
817
818 int
819 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
820 struct mbuf *m0,
821 bus_dmamap_callback2_t *callback, void *callback_arg,
822 int flags)
823 {
824 int nsegs, error;
825
826 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs,
827 flags);
828
829 if (error) {
830 /* force "no valid mappings" in callback */
831 (*callback)(callback_arg, dmat->segments, 0, 0, error);
832 } else {
833 (*callback)(callback_arg, dmat->segments,
834 nsegs, m0->m_pkthdr.len, error);
835 }
836 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
837 __func__, dmat, dmat->flags, error, nsegs);
838 return (error);
839 }
840
841 int
842 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
843 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
844 int flags)
845 {
846 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags));
847 }
848
849 /*
850 * Like _bus_dmamap_load(), but for uios.
851 */
852 int
853 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
854 struct uio *uio,
855 bus_dmamap_callback2_t *callback, void *callback_arg,
856 int flags)
857 {
858 bus_addr_t lastaddr;
859 int nsegs, error, first, i;
860 bus_size_t resid;
861 struct iovec *iov;
862 pmap_t pmap;
863
864 flags |= BUS_DMA_NOWAIT;
865 resid = uio->uio_resid;
866 iov = uio->uio_iov;
867
868 if (uio->uio_segflg == UIO_USERSPACE) {
869 KASSERT(uio->uio_td != NULL,
870 ("bus_dmamap_load_uio: USERSPACE but no proc"));
871 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
872 } else
873 pmap = NULL;
874
875 nsegs = 0;
876 error = 0;
877 first = 1;
878 lastaddr = (bus_addr_t) 0;
879 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
880 /*
881 * Now at the first iovec to load. Load each iovec
882 * until we have exhausted the residual count.
883 */
884 bus_size_t minlen =
885 resid < iov[i].iov_len ? resid : iov[i].iov_len;
886 caddr_t addr = (caddr_t) iov[i].iov_base;
887
888 if (minlen > 0) {
889 error = _bus_dmamap_load_buffer(dmat, map,
890 addr, minlen, pmap, flags, &lastaddr,
891 dmat->segments, &nsegs, first);
892 first = 0;
893
894 resid -= minlen;
895 }
896 }
897
898 if (error) {
899 /* force "no valid mappings" in callback */
900 (*callback)(callback_arg, dmat->segments, 0, 0, error);
901 } else {
902 (*callback)(callback_arg, dmat->segments,
903 nsegs+1, uio->uio_resid, error);
904 }
905 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
906 __func__, dmat, dmat->flags, error, nsegs + 1);
907 return (error);
908 }
909
910 /*
911 * Release the mapping held by map.
912 */
913 void
914 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
915 {
916 struct bounce_page *bpage;
917
918 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
919 STAILQ_REMOVE_HEAD(&map->bpages, links);
920 free_bounce_page(dmat, bpage);
921 }
922 }
923
924 void
925 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
926 {
927 struct bounce_page *bpage;
928
929 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
930 /*
931 * Handle data bouncing. We might also
932 * want to add support for invalidating
933 * the caches on broken hardware
934 */
935 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
936 "performing bounce", __func__, op, dmat, dmat->flags);
937
938 if (op & BUS_DMASYNC_PREWRITE) {
939 while (bpage != NULL) {
940 bcopy((void *)bpage->datavaddr,
941 (void *)bpage->vaddr,
942 bpage->datacount);
943 bpage = STAILQ_NEXT(bpage, links);
944 }
945 dmat->bounce_zone->total_bounced++;
946 }
947
948 if (op & BUS_DMASYNC_POSTREAD) {
949 while (bpage != NULL) {
950 bcopy((void *)bpage->vaddr,
951 (void *)bpage->datavaddr,
952 bpage->datacount);
953 bpage = STAILQ_NEXT(bpage, links);
954 }
955 dmat->bounce_zone->total_bounced++;
956 }
957 }
958 }
959
960 static void
961 init_bounce_pages(void *dummy __unused)
962 {
963
964 total_bpages = 0;
965 STAILQ_INIT(&bounce_zone_list);
966 STAILQ_INIT(&bounce_map_waitinglist);
967 STAILQ_INIT(&bounce_map_callbacklist);
968 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
969 }
970 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
971
972 static struct sysctl_ctx_list *
973 busdma_sysctl_tree(struct bounce_zone *bz)
974 {
975 return (&bz->sysctl_tree);
976 }
977
978 static struct sysctl_oid *
979 busdma_sysctl_tree_top(struct bounce_zone *bz)
980 {
981 return (bz->sysctl_tree_top);
982 }
983
984 static int
985 alloc_bounce_zone(bus_dma_tag_t dmat)
986 {
987 struct bounce_zone *bz;
988
989 /* Check to see if we already have a suitable zone */
990 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
991 if ((dmat->alignment <= bz->alignment)
992 && (dmat->boundary <= bz->boundary)
993 && (dmat->lowaddr >= bz->lowaddr)) {
994 dmat->bounce_zone = bz;
995 return (0);
996 }
997 }
998
999 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1000 M_NOWAIT | M_ZERO)) == NULL)
1001 return (ENOMEM);
1002
1003 STAILQ_INIT(&bz->bounce_page_list);
1004 bz->free_bpages = 0;
1005 bz->reserved_bpages = 0;
1006 bz->active_bpages = 0;
1007 bz->lowaddr = dmat->lowaddr;
1008 bz->alignment = dmat->alignment;
1009 bz->boundary = dmat->boundary;
1010 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1011 busdma_zonecount++;
1012 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1013 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1014 dmat->bounce_zone = bz;
1015
1016 sysctl_ctx_init(&bz->sysctl_tree);
1017 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1018 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1019 CTLFLAG_RD, 0, "");
1020 if (bz->sysctl_tree_top == NULL) {
1021 sysctl_ctx_free(&bz->sysctl_tree);
1022 return (0); /* XXX error code? */
1023 }
1024
1025 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1026 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1027 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1028 "Total bounce pages");
1029 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1030 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1031 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1032 "Free bounce pages");
1033 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1034 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1035 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1036 "Reserved bounce pages");
1037 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1038 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1039 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1040 "Active bounce pages");
1041 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1042 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1043 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1044 "Total bounce requests");
1045 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1046 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1047 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1048 "Total bounce requests that were deferred");
1049 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1050 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1051 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1052 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1053 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1054 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1055 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1056 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1057 "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
1058
1059 return (0);
1060 }
1061
1062 static int
1063 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1064 {
1065 struct bounce_zone *bz;
1066 int count;
1067
1068 bz = dmat->bounce_zone;
1069 count = 0;
1070 while (numpages > 0) {
1071 struct bounce_page *bpage;
1072
1073 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1074 M_NOWAIT | M_ZERO);
1075
1076 if (bpage == NULL)
1077 break;
1078 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1079 M_NOWAIT, 0ul,
1080 bz->lowaddr,
1081 PAGE_SIZE,
1082 bz->boundary);
1083 if (bpage->vaddr == 0) {
1084 free(bpage, M_DEVBUF);
1085 break;
1086 }
1087 bpage->busaddr = pmap_kextract(bpage->vaddr);
1088 mtx_lock(&bounce_lock);
1089 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1090 total_bpages++;
1091 bz->total_bpages++;
1092 bz->free_bpages++;
1093 mtx_unlock(&bounce_lock);
1094 count++;
1095 numpages--;
1096 }
1097 return (count);
1098 }
1099
1100 static int
1101 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1102 {
1103 struct bounce_zone *bz;
1104 int pages;
1105
1106 mtx_assert(&bounce_lock, MA_OWNED);
1107 bz = dmat->bounce_zone;
1108 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1109 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1110 return (map->pagesneeded - (map->pagesreserved + pages));
1111 bz->free_bpages -= pages;
1112 bz->reserved_bpages += pages;
1113 map->pagesreserved += pages;
1114 pages = map->pagesneeded - map->pagesreserved;
1115
1116 return (pages);
1117 }
1118
1119 static bus_addr_t
1120 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1121 bus_size_t size)
1122 {
1123 struct bounce_zone *bz;
1124 struct bounce_page *bpage;
1125
1126 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1127 KASSERT(map != NULL && map != &nobounce_dmamap,
1128 ("add_bounce_page: bad map %p", map));
1129
1130 bz = dmat->bounce_zone;
1131 if (map->pagesneeded == 0)
1132 panic("add_bounce_page: map doesn't need any pages");
1133 map->pagesneeded--;
1134
1135 if (map->pagesreserved == 0)
1136 panic("add_bounce_page: map doesn't need any pages");
1137 map->pagesreserved--;
1138
1139 mtx_lock(&bounce_lock);
1140 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1141 if (bpage == NULL)
1142 panic("add_bounce_page: free page list is empty");
1143
1144 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1145 bz->reserved_bpages--;
1146 bz->active_bpages++;
1147 mtx_unlock(&bounce_lock);
1148
1149 bpage->datavaddr = vaddr;
1150 bpage->datacount = size;
1151 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1152 return (bpage->busaddr);
1153 }
1154
1155 static void
1156 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1157 {
1158 struct bus_dmamap *map;
1159 struct bounce_zone *bz;
1160
1161 bz = dmat->bounce_zone;
1162 bpage->datavaddr = 0;
1163 bpage->datacount = 0;
1164
1165 mtx_lock(&bounce_lock);
1166 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1167 bz->free_bpages++;
1168 bz->active_bpages--;
1169 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1170 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1171 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1172 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1173 map, links);
1174 busdma_swi_pending = 1;
1175 bz->total_deferred++;
1176 swi_sched(vm_ih, 0);
1177 }
1178 }
1179 mtx_unlock(&bounce_lock);
1180 }
1181
1182 void
1183 busdma_swi(void)
1184 {
1185 bus_dma_tag_t dmat;
1186 struct bus_dmamap *map;
1187
1188 mtx_lock(&bounce_lock);
1189 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1190 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1191 mtx_unlock(&bounce_lock);
1192 dmat = map->dmat;
1193 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1194 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1195 map->callback, map->callback_arg, /*flags*/0);
1196 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1197 mtx_lock(&bounce_lock);
1198 }
1199 mtx_unlock(&bounce_lock);
1200 }
Cache object: 9a2d6256f8e8d67505d5f8d2946168ab
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