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 int map_count;
97 bus_size_t alignment;
98 bus_addr_t lowaddr;
99 char zoneid[8];
100 char lowaddrid[20];
101 struct sysctl_ctx_list sysctl_tree;
102 struct sysctl_oid *sysctl_tree_top;
103 };
104
105 static struct mtx bounce_lock;
106 static int total_bpages;
107 static int busdma_zonecount;
108 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
109
110 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
111 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
112 "Total bounce pages");
113
114 struct bus_dmamap {
115 struct bp_list bpages;
116 int pagesneeded;
117 int pagesreserved;
118 bus_dma_tag_t dmat;
119 void *buf; /* unmapped buffer pointer */
120 bus_size_t buflen; /* unmapped buffer length */
121 bus_dmamap_callback_t *callback;
122 void *callback_arg;
123 STAILQ_ENTRY(bus_dmamap) links;
124 };
125
126 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
127 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
128 static struct bus_dmamap nobounce_dmamap;
129
130 static void init_bounce_pages(void *dummy);
131 static int alloc_bounce_zone(bus_dma_tag_t dmat);
132 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
133 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
134 int commit);
135 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
136 vm_offset_t vaddr, bus_size_t size);
137 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
138 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
139
140 /*
141 * Return true if a match is made.
142 *
143 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
144 *
145 * If paddr is within the bounds of the dma tag then call the filter callback
146 * to check for a match, if there is no filter callback then assume a match.
147 */
148 static __inline int
149 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
150 {
151 int retval;
152
153 retval = 0;
154
155 do {
156 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
157 || ((paddr & (dmat->alignment - 1)) != 0))
158 && (dmat->filter == NULL
159 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
160 retval = 1;
161
162 dmat = dmat->parent;
163 } while (retval == 0 && dmat != NULL);
164 return (retval);
165 }
166
167 /*
168 * Convenience function for manipulating driver locks from busdma (during
169 * busdma_swi, for example). Drivers that don't provide their own locks
170 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
171 * non-mutex locking scheme don't have to use this at all.
172 */
173 void
174 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
175 {
176 struct mtx *dmtx;
177
178 dmtx = (struct mtx *)arg;
179 switch (op) {
180 case BUS_DMA_LOCK:
181 mtx_lock(dmtx);
182 break;
183 case BUS_DMA_UNLOCK:
184 mtx_unlock(dmtx);
185 break;
186 default:
187 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
188 }
189 }
190
191 /*
192 * dflt_lock should never get called. It gets put into the dma tag when
193 * lockfunc == NULL, which is only valid if the maps that are associated
194 * with the tag are meant to never be defered.
195 * XXX Should have a way to identify which driver is responsible here.
196 */
197 static void
198 dflt_lock(void *arg, bus_dma_lock_op_t op)
199 {
200 panic("driver error: busdma dflt_lock called");
201 }
202
203 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
204 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
205 /*
206 * Allocate a device specific dma_tag.
207 */
208 int
209 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
210 bus_size_t boundary, bus_addr_t lowaddr,
211 bus_addr_t highaddr, bus_dma_filter_t *filter,
212 void *filterarg, bus_size_t maxsize, int nsegments,
213 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
214 void *lockfuncarg, bus_dma_tag_t *dmat)
215 {
216 bus_dma_tag_t newtag;
217 int error = 0;
218
219 /* Always enforce at least a 4GB boundary. */
220 if (boundary == 0 || boundary > ((bus_addr_t)1 << 32))
221 boundary = (bus_size_t)1 << 32;
222
223 /* Basic sanity checking */
224 if (boundary != 0 && boundary < maxsegsz)
225 maxsegsz = boundary;
226
227 if (maxsegsz == 0) {
228 return (EINVAL);
229 }
230
231 /* Return a NULL tag on failure */
232 *dmat = NULL;
233
234 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
235 M_ZERO | M_NOWAIT);
236 if (newtag == NULL) {
237 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
238 __func__, newtag, 0, ENOMEM);
239 return (ENOMEM);
240 }
241
242 newtag->parent = parent;
243 newtag->alignment = alignment;
244 newtag->boundary = boundary;
245 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
246 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
247 newtag->filter = filter;
248 newtag->filterarg = filterarg;
249 newtag->maxsize = maxsize;
250 newtag->nsegments = nsegments;
251 newtag->maxsegsz = maxsegsz;
252 newtag->flags = flags;
253 newtag->ref_count = 1; /* Count ourself */
254 newtag->map_count = 0;
255 if (lockfunc != NULL) {
256 newtag->lockfunc = lockfunc;
257 newtag->lockfuncarg = lockfuncarg;
258 } else {
259 newtag->lockfunc = dflt_lock;
260 newtag->lockfuncarg = NULL;
261 }
262 newtag->segments = NULL;
263
264 /* Take into account any restrictions imposed by our parent tag */
265 if (parent != NULL) {
266 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
267 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
268 if (newtag->boundary == 0)
269 newtag->boundary = parent->boundary;
270 else if (parent->boundary != 0)
271 newtag->boundary = MIN(parent->boundary,
272 newtag->boundary);
273 if (newtag->filter == NULL) {
274 /*
275 * Short circuit looking at our parent directly
276 * since we have encapsulated all of its information
277 */
278 newtag->filter = parent->filter;
279 newtag->filterarg = parent->filterarg;
280 newtag->parent = parent->parent;
281 }
282 if (newtag->parent != NULL)
283 atomic_add_int(&parent->ref_count, 1);
284 }
285
286 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
287 || newtag->alignment > 1)
288 newtag->flags |= BUS_DMA_COULD_BOUNCE;
289
290 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
291 (flags & BUS_DMA_ALLOCNOW) != 0) {
292 struct bounce_zone *bz;
293
294 /* Must bounce */
295
296 if ((error = alloc_bounce_zone(newtag)) != 0) {
297 free(newtag, M_DEVBUF);
298 return (error);
299 }
300 bz = newtag->bounce_zone;
301
302 if (ptoa(bz->total_bpages) < maxsize) {
303 int pages;
304
305 pages = atop(maxsize) - bz->total_bpages;
306
307 /* Add pages to our bounce pool */
308 if (alloc_bounce_pages(newtag, pages) < pages)
309 error = ENOMEM;
310 }
311 /* Performed initial allocation */
312 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
313 }
314
315 if (error != 0) {
316 free(newtag, M_DEVBUF);
317 } else {
318 *dmat = newtag;
319 }
320 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
321 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
322 return (error);
323 }
324
325 int
326 bus_dma_tag_destroy(bus_dma_tag_t dmat)
327 {
328 bus_dma_tag_t dmat_copy;
329 int error;
330
331 error = 0;
332 dmat_copy = dmat;
333
334 if (dmat != NULL) {
335
336 if (dmat->map_count != 0) {
337 error = EBUSY;
338 goto out;
339 }
340
341 while (dmat != NULL) {
342 bus_dma_tag_t parent;
343
344 parent = dmat->parent;
345 atomic_subtract_int(&dmat->ref_count, 1);
346 if (dmat->ref_count == 0) {
347 if (dmat->segments != NULL)
348 free(dmat->segments, M_DEVBUF);
349 free(dmat, M_DEVBUF);
350 /*
351 * Last reference count, so
352 * release our reference
353 * count on our parent.
354 */
355 dmat = parent;
356 } else
357 dmat = NULL;
358 }
359 }
360 out:
361 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
362 return (error);
363 }
364
365 /*
366 * Allocate a handle for mapping from kva/uva/physical
367 * address space into bus device space.
368 */
369 int
370 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
371 {
372 int error;
373
374 error = 0;
375
376 if (dmat->segments == NULL) {
377 dmat->segments = (bus_dma_segment_t *)malloc(
378 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
379 M_NOWAIT);
380 if (dmat->segments == NULL) {
381 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
382 __func__, dmat, ENOMEM);
383 return (ENOMEM);
384 }
385 }
386
387 /*
388 * Bouncing might be required if the driver asks for an active
389 * exclusion region, a data alignment that is stricter than 1, and/or
390 * an active address boundary.
391 */
392 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
393
394 /* Must bounce */
395 struct bounce_zone *bz;
396 int maxpages;
397
398 if (dmat->bounce_zone == NULL) {
399 if ((error = alloc_bounce_zone(dmat)) != 0)
400 return (error);
401 }
402 bz = dmat->bounce_zone;
403
404 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
405 M_NOWAIT | M_ZERO);
406 if (*mapp == NULL) {
407 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
408 __func__, dmat, ENOMEM);
409 return (ENOMEM);
410 }
411
412 /* Initialize the new map */
413 STAILQ_INIT(&((*mapp)->bpages));
414
415 /*
416 * Attempt to add pages to our pool on a per-instance
417 * basis up to a sane limit.
418 */
419 if (dmat->alignment > 1)
420 maxpages = MAX_BPAGES;
421 else
422 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
423 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
424 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
425 int pages;
426
427 pages = MAX(atop(dmat->maxsize), 1);
428 pages = MIN(maxpages - bz->total_bpages, pages);
429 pages = MAX(pages, 1);
430 if (alloc_bounce_pages(dmat, pages) < pages)
431 error = ENOMEM;
432
433 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
434 if (error == 0)
435 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
436 } else {
437 error = 0;
438 }
439 }
440 bz->map_count++;
441 } else {
442 *mapp = NULL;
443 }
444 if (error == 0)
445 dmat->map_count++;
446 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
447 __func__, dmat, dmat->flags, error);
448 return (error);
449 }
450
451 /*
452 * Destroy a handle for mapping from kva/uva/physical
453 * address space into bus device space.
454 */
455 int
456 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
457 {
458 if (map != NULL && map != &nobounce_dmamap) {
459 if (STAILQ_FIRST(&map->bpages) != NULL) {
460 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
461 __func__, dmat, EBUSY);
462 return (EBUSY);
463 }
464 if (dmat->bounce_zone)
465 dmat->bounce_zone->map_count--;
466 free(map, M_DEVBUF);
467 }
468 dmat->map_count--;
469 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
470 return (0);
471 }
472
473
474 /*
475 * Allocate a piece of memory that can be efficiently mapped into
476 * bus device space based on the constraints lited in the dma tag.
477 * A dmamap to for use with dmamap_load is also allocated.
478 */
479 int
480 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
481 bus_dmamap_t *mapp)
482 {
483 int mflags;
484
485 if (flags & BUS_DMA_NOWAIT)
486 mflags = M_NOWAIT;
487 else
488 mflags = M_WAITOK;
489
490 /* If we succeed, no mapping/bouncing will be required */
491 *mapp = NULL;
492
493 if (dmat->segments == NULL) {
494 dmat->segments = (bus_dma_segment_t *)malloc(
495 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
496 mflags);
497 if (dmat->segments == NULL) {
498 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
499 __func__, dmat, dmat->flags, ENOMEM);
500 return (ENOMEM);
501 }
502 }
503 if (flags & BUS_DMA_ZERO)
504 mflags |= M_ZERO;
505
506 /*
507 * XXX:
508 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
509 * alignment guarantees of malloc need to be nailed down, and the
510 * code below should be rewritten to take that into account.
511 *
512 * In the meantime, we'll warn the user if malloc gets it wrong.
513 */
514 if ((dmat->maxsize <= PAGE_SIZE) &&
515 (dmat->alignment < dmat->maxsize) &&
516 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
517 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
518 } else {
519 /*
520 * XXX Use Contigmalloc until it is merged into this facility
521 * and handles multi-seg allocations. Nobody is doing
522 * multi-seg allocations yet though.
523 * XXX Certain AGP hardware does.
524 */
525 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
526 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
527 dmat->boundary);
528 }
529 if (*vaddr == NULL) {
530 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
531 __func__, dmat, dmat->flags, ENOMEM);
532 return (ENOMEM);
533 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
534 printf("bus_dmamem_alloc failed to align memory properly.\n");
535 }
536 if (flags & BUS_DMA_NOCACHE)
537 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
538 PAT_UNCACHEABLE);
539 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
540 __func__, dmat, dmat->flags, 0);
541 return (0);
542 }
543
544 /*
545 * Free a piece of memory and it's allociated dmamap, that was allocated
546 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
547 */
548 void
549 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
550 {
551 /*
552 * dmamem does not need to be bounced, so the map should be
553 * NULL
554 */
555 if (map != NULL)
556 panic("bus_dmamem_free: Invalid map freed\n");
557 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
558 if ((dmat->maxsize <= PAGE_SIZE) &&
559 (dmat->alignment < dmat->maxsize) &&
560 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
561 free(vaddr, M_DEVBUF);
562 else {
563 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
564 }
565 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
566 }
567
568 /*
569 * Utility function to load a linear buffer. lastaddrp holds state
570 * between invocations (for multiple-buffer loads). segp contains
571 * the starting segment on entrace, and the ending segment on exit.
572 * first indicates if this is the first invocation of this function.
573 */
574 static __inline int
575 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
576 bus_dmamap_t map,
577 void *buf, bus_size_t buflen,
578 pmap_t pmap,
579 int flags,
580 bus_addr_t *lastaddrp,
581 bus_dma_segment_t *segs,
582 int *segp,
583 int first)
584 {
585 bus_size_t sgsize;
586 bus_addr_t curaddr, lastaddr, baddr, bmask;
587 vm_offset_t vaddr;
588 bus_addr_t paddr;
589 int seg;
590
591 if (map == NULL)
592 map = &nobounce_dmamap;
593
594 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
595 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
596 vm_offset_t vendaddr;
597
598 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
599 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
600 dmat->boundary, dmat->alignment);
601 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
602 map, &nobounce_dmamap, map->pagesneeded);
603 /*
604 * Count the number of bounce pages
605 * needed in order to complete this transfer
606 */
607 vaddr = (vm_offset_t)buf;
608 vendaddr = (vm_offset_t)buf + buflen;
609
610 while (vaddr < vendaddr) {
611 bus_size_t sg_len;
612
613 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
614 if (pmap)
615 paddr = pmap_extract(pmap, vaddr);
616 else
617 paddr = pmap_kextract(vaddr);
618 if (run_filter(dmat, paddr) != 0) {
619 sg_len = roundup2(sg_len, dmat->alignment);
620 map->pagesneeded++;
621 }
622 vaddr += sg_len;
623 }
624 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
625 }
626
627 /* Reserve Necessary Bounce Pages */
628 if (map->pagesneeded != 0) {
629 mtx_lock(&bounce_lock);
630 if (flags & BUS_DMA_NOWAIT) {
631 if (reserve_bounce_pages(dmat, map, 0) != 0) {
632 mtx_unlock(&bounce_lock);
633 return (ENOMEM);
634 }
635 } else {
636 if (reserve_bounce_pages(dmat, map, 1) != 0) {
637 /* Queue us for resources */
638 map->dmat = dmat;
639 map->buf = buf;
640 map->buflen = buflen;
641 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
642 map, links);
643 mtx_unlock(&bounce_lock);
644 return (EINPROGRESS);
645 }
646 }
647 mtx_unlock(&bounce_lock);
648 }
649
650 vaddr = (vm_offset_t)buf;
651 lastaddr = *lastaddrp;
652 bmask = ~(dmat->boundary - 1);
653
654 for (seg = *segp; buflen > 0 ; ) {
655 bus_size_t max_sgsize;
656
657 /*
658 * Get the physical address for this segment.
659 */
660 if (pmap)
661 curaddr = pmap_extract(pmap, vaddr);
662 else
663 curaddr = pmap_kextract(vaddr);
664
665 /*
666 * Compute the segment size, and adjust counts.
667 */
668 max_sgsize = MIN(buflen, dmat->maxsegsz);
669 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
670 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
671 sgsize = roundup2(sgsize, dmat->alignment);
672 sgsize = MIN(sgsize, max_sgsize);
673 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
674 } else {
675 sgsize = MIN(sgsize, max_sgsize);
676 }
677
678 /*
679 * Make sure we don't cross any boundaries.
680 */
681 if (dmat->boundary > 0) {
682 baddr = (curaddr + dmat->boundary) & bmask;
683 if (sgsize > (baddr - curaddr))
684 sgsize = (baddr - curaddr);
685 }
686
687 /*
688 * Insert chunk into a segment, coalescing with
689 * previous segment if possible.
690 */
691 if (first) {
692 segs[seg].ds_addr = curaddr;
693 segs[seg].ds_len = sgsize;
694 first = 0;
695 } else {
696 if (curaddr == lastaddr &&
697 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
698 (dmat->boundary == 0 ||
699 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
700 segs[seg].ds_len += sgsize;
701 else {
702 if (++seg >= dmat->nsegments)
703 break;
704 segs[seg].ds_addr = curaddr;
705 segs[seg].ds_len = sgsize;
706 }
707 }
708
709 lastaddr = curaddr + sgsize;
710 vaddr += sgsize;
711 buflen -= sgsize;
712 }
713
714 *segp = seg;
715 *lastaddrp = lastaddr;
716
717 /*
718 * Did we fit?
719 */
720 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
721 }
722
723 /*
724 * Map the buffer buf into bus space using the dmamap map.
725 */
726 int
727 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
728 bus_size_t buflen, bus_dmamap_callback_t *callback,
729 void *callback_arg, int flags)
730 {
731 bus_addr_t lastaddr = 0;
732 int error, nsegs = 0;
733
734 if (map != NULL) {
735 flags |= BUS_DMA_WAITOK;
736 map->callback = callback;
737 map->callback_arg = callback_arg;
738 }
739
740 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
741 &lastaddr, dmat->segments, &nsegs, 1);
742
743 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
744 __func__, dmat, dmat->flags, error, nsegs + 1);
745
746 if (error == EINPROGRESS) {
747 return (error);
748 }
749
750 if (error)
751 (*callback)(callback_arg, dmat->segments, 0, error);
752 else
753 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
754
755 /*
756 * Return ENOMEM to the caller so that it can pass it up the stack.
757 * This error only happens when NOWAIT is set, so deferal is disabled.
758 */
759 if (error == ENOMEM)
760 return (error);
761
762 return (0);
763 }
764
765
766 /*
767 * Like _bus_dmamap_load(), but for mbufs.
768 */
769 int
770 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
771 struct mbuf *m0,
772 bus_dmamap_callback2_t *callback, void *callback_arg,
773 int flags)
774 {
775 int nsegs, error;
776
777 M_ASSERTPKTHDR(m0);
778
779 flags |= BUS_DMA_NOWAIT;
780 nsegs = 0;
781 error = 0;
782 if (m0->m_pkthdr.len <= dmat->maxsize) {
783 int first = 1;
784 bus_addr_t lastaddr = 0;
785 struct mbuf *m;
786
787 for (m = m0; m != NULL && error == 0; m = m->m_next) {
788 if (m->m_len > 0) {
789 error = _bus_dmamap_load_buffer(dmat, map,
790 m->m_data, m->m_len,
791 NULL, flags, &lastaddr,
792 dmat->segments, &nsegs, first);
793 first = 0;
794 }
795 }
796 } else {
797 error = EINVAL;
798 }
799
800 if (error) {
801 /* force "no valid mappings" in callback */
802 (*callback)(callback_arg, dmat->segments, 0, 0, error);
803 } else {
804 (*callback)(callback_arg, dmat->segments,
805 nsegs+1, m0->m_pkthdr.len, error);
806 }
807 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
808 __func__, dmat, dmat->flags, error, nsegs + 1);
809 return (error);
810 }
811
812 int
813 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
814 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
815 int flags)
816 {
817 int error;
818
819 M_ASSERTPKTHDR(m0);
820
821 flags |= BUS_DMA_NOWAIT;
822 *nsegs = 0;
823 error = 0;
824 if (m0->m_pkthdr.len <= dmat->maxsize) {
825 int first = 1;
826 bus_addr_t lastaddr = 0;
827 struct mbuf *m;
828
829 for (m = m0; m != NULL && error == 0; m = m->m_next) {
830 if (m->m_len > 0) {
831 error = _bus_dmamap_load_buffer(dmat, map,
832 m->m_data, m->m_len,
833 NULL, flags, &lastaddr,
834 segs, nsegs, first);
835 first = 0;
836 }
837 }
838 } else {
839 error = EINVAL;
840 }
841
842 /* XXX FIXME: Having to increment nsegs is really annoying */
843 ++*nsegs;
844 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
845 __func__, dmat, dmat->flags, error, *nsegs);
846 return (error);
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 = 0;
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 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
879 /*
880 * Now at the first iovec to load. Load each iovec
881 * until we have exhausted the residual count.
882 */
883 bus_size_t minlen =
884 resid < iov[i].iov_len ? resid : iov[i].iov_len;
885 caddr_t addr = (caddr_t) iov[i].iov_base;
886
887 if (minlen > 0) {
888 error = _bus_dmamap_load_buffer(dmat, map,
889 addr, minlen, pmap, flags, &lastaddr,
890 dmat->segments, &nsegs, first);
891 first = 0;
892
893 resid -= minlen;
894 }
895 }
896
897 if (error) {
898 /* force "no valid mappings" in callback */
899 (*callback)(callback_arg, dmat->segments, 0, 0, error);
900 } else {
901 (*callback)(callback_arg, dmat->segments,
902 nsegs+1, uio->uio_resid, error);
903 }
904 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
905 __func__, dmat, dmat->flags, error, nsegs + 1);
906 return (error);
907 }
908
909 /*
910 * Release the mapping held by map.
911 */
912 void
913 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
914 {
915 struct bounce_page *bpage;
916
917 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
918 STAILQ_REMOVE_HEAD(&map->bpages, links);
919 free_bounce_page(dmat, bpage);
920 }
921 }
922
923 void
924 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
925 {
926 struct bounce_page *bpage;
927
928 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
929 /*
930 * Handle data bouncing. We might also
931 * want to add support for invalidating
932 * the caches on broken hardware
933 */
934 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
935 "performing bounce", __func__, op, dmat, dmat->flags);
936
937 if (op & BUS_DMASYNC_PREWRITE) {
938 while (bpage != NULL) {
939 bcopy((void *)bpage->datavaddr,
940 (void *)bpage->vaddr,
941 bpage->datacount);
942 bpage = STAILQ_NEXT(bpage, links);
943 }
944 dmat->bounce_zone->total_bounced++;
945 }
946
947 if (op & BUS_DMASYNC_POSTREAD) {
948 while (bpage != NULL) {
949 bcopy((void *)bpage->vaddr,
950 (void *)bpage->datavaddr,
951 bpage->datacount);
952 bpage = STAILQ_NEXT(bpage, links);
953 }
954 dmat->bounce_zone->total_bounced++;
955 }
956 }
957 }
958
959 static void
960 init_bounce_pages(void *dummy __unused)
961 {
962
963 total_bpages = 0;
964 STAILQ_INIT(&bounce_zone_list);
965 STAILQ_INIT(&bounce_map_waitinglist);
966 STAILQ_INIT(&bounce_map_callbacklist);
967 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
968 }
969 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
970
971 static struct sysctl_ctx_list *
972 busdma_sysctl_tree(struct bounce_zone *bz)
973 {
974 return (&bz->sysctl_tree);
975 }
976
977 static struct sysctl_oid *
978 busdma_sysctl_tree_top(struct bounce_zone *bz)
979 {
980 return (bz->sysctl_tree_top);
981 }
982
983 static int
984 alloc_bounce_zone(bus_dma_tag_t dmat)
985 {
986 struct bounce_zone *bz;
987
988 /* Check to see if we already have a suitable zone */
989 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
990 if ((dmat->alignment <= bz->alignment)
991 && (dmat->lowaddr >= bz->lowaddr)) {
992 dmat->bounce_zone = bz;
993 return (0);
994 }
995 }
996
997 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
998 M_NOWAIT | M_ZERO)) == NULL)
999 return (ENOMEM);
1000
1001 STAILQ_INIT(&bz->bounce_page_list);
1002 bz->free_bpages = 0;
1003 bz->reserved_bpages = 0;
1004 bz->active_bpages = 0;
1005 bz->lowaddr = dmat->lowaddr;
1006 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1007 bz->map_count = 0;
1008 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1009 busdma_zonecount++;
1010 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1011 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1012 dmat->bounce_zone = bz;
1013
1014 sysctl_ctx_init(&bz->sysctl_tree);
1015 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1016 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1017 CTLFLAG_RD, 0, "");
1018 if (bz->sysctl_tree_top == NULL) {
1019 sysctl_ctx_free(&bz->sysctl_tree);
1020 return (0); /* XXX error code? */
1021 }
1022
1023 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1024 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1025 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1026 "Total bounce pages");
1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1029 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1030 "Free bounce pages");
1031 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1032 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1033 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1034 "Reserved bounce pages");
1035 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1036 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1037 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1038 "Active bounce pages");
1039 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1040 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1041 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1042 "Total bounce requests");
1043 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1044 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1045 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1046 "Total bounce requests that were deferred");
1047 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1048 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1049 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1050 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1051 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1052 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1053
1054 return (0);
1055 }
1056
1057 static int
1058 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1059 {
1060 struct bounce_zone *bz;
1061 int count;
1062
1063 bz = dmat->bounce_zone;
1064 count = 0;
1065 while (numpages > 0) {
1066 struct bounce_page *bpage;
1067
1068 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1069 M_NOWAIT | M_ZERO);
1070
1071 if (bpage == NULL)
1072 break;
1073 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1074 M_NOWAIT, 0ul,
1075 bz->lowaddr,
1076 PAGE_SIZE,
1077 0);
1078 if (bpage->vaddr == 0) {
1079 free(bpage, M_DEVBUF);
1080 break;
1081 }
1082 bpage->busaddr = pmap_kextract(bpage->vaddr);
1083 mtx_lock(&bounce_lock);
1084 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1085 total_bpages++;
1086 bz->total_bpages++;
1087 bz->free_bpages++;
1088 mtx_unlock(&bounce_lock);
1089 count++;
1090 numpages--;
1091 }
1092 return (count);
1093 }
1094
1095 static int
1096 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1097 {
1098 struct bounce_zone *bz;
1099 int pages;
1100
1101 mtx_assert(&bounce_lock, MA_OWNED);
1102 bz = dmat->bounce_zone;
1103 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1104 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1105 return (map->pagesneeded - (map->pagesreserved + pages));
1106 bz->free_bpages -= pages;
1107 bz->reserved_bpages += pages;
1108 map->pagesreserved += pages;
1109 pages = map->pagesneeded - map->pagesreserved;
1110
1111 return (pages);
1112 }
1113
1114 static bus_addr_t
1115 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1116 bus_size_t size)
1117 {
1118 struct bounce_zone *bz;
1119 struct bounce_page *bpage;
1120
1121 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1122 KASSERT(map != NULL && map != &nobounce_dmamap,
1123 ("add_bounce_page: bad map %p", map));
1124
1125 bz = dmat->bounce_zone;
1126 if (map->pagesneeded == 0)
1127 panic("add_bounce_page: map doesn't need any pages");
1128 map->pagesneeded--;
1129
1130 if (map->pagesreserved == 0)
1131 panic("add_bounce_page: map doesn't need any pages");
1132 map->pagesreserved--;
1133
1134 mtx_lock(&bounce_lock);
1135 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1136 if (bpage == NULL)
1137 panic("add_bounce_page: free page list is empty");
1138
1139 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1140 bz->reserved_bpages--;
1141 bz->active_bpages++;
1142 mtx_unlock(&bounce_lock);
1143
1144 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1145 /* Page offset needs to be preserved. */
1146 bpage->vaddr |= vaddr & PAGE_MASK;
1147 bpage->busaddr |= vaddr & PAGE_MASK;
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 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1165 /*
1166 * Reset the bounce page to start at offset 0. Other uses
1167 * of this bounce page may need to store a full page of
1168 * data and/or assume it starts on a page boundary.
1169 */
1170 bpage->vaddr &= ~PAGE_MASK;
1171 bpage->busaddr &= ~PAGE_MASK;
1172 }
1173
1174 mtx_lock(&bounce_lock);
1175 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1176 bz->free_bpages++;
1177 bz->active_bpages--;
1178 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1179 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1180 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1181 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1182 map, links);
1183 busdma_swi_pending = 1;
1184 bz->total_deferred++;
1185 swi_sched(vm_ih, 0);
1186 }
1187 }
1188 mtx_unlock(&bounce_lock);
1189 }
1190
1191 void
1192 busdma_swi(void)
1193 {
1194 bus_dma_tag_t dmat;
1195 struct bus_dmamap *map;
1196
1197 mtx_lock(&bounce_lock);
1198 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1199 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1200 mtx_unlock(&bounce_lock);
1201 dmat = map->dmat;
1202 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1203 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1204 map->callback, map->callback_arg, /*flags*/0);
1205 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1206 mtx_lock(&bounce_lock);
1207 }
1208 mtx_unlock(&bounce_lock);
1209 }
Cache object: 28ba15ee8f6dc990ade2d1f98c76541f
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