1 /*-
2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions, and the following disclaimer,
10 * without modification, immediately at the beginning of the file.
11 * 2. The name of the author may not be used to endorse or promote products
12 * derived from this software without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
18 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: releng/6.4/sys/amd64/amd64/busdma_machdep.c 177306 2008-03-17 17:33:32Z jhb $");
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 /* Return a NULL tag on failure */
224 *dmat = NULL;
225
226 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
227 M_ZERO | M_NOWAIT);
228 if (newtag == NULL) {
229 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
230 __func__, newtag, 0, error);
231 return (ENOMEM);
232 }
233
234 newtag->parent = parent;
235 newtag->alignment = alignment;
236 newtag->boundary = boundary;
237 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
238 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) +
239 (PAGE_SIZE - 1);
240 newtag->filter = filter;
241 newtag->filterarg = filterarg;
242 newtag->maxsize = maxsize;
243 newtag->nsegments = nsegments;
244 newtag->maxsegsz = maxsegsz;
245 newtag->flags = flags;
246 newtag->ref_count = 1; /* Count ourself */
247 newtag->map_count = 0;
248 if (lockfunc != NULL) {
249 newtag->lockfunc = lockfunc;
250 newtag->lockfuncarg = lockfuncarg;
251 } else {
252 newtag->lockfunc = dflt_lock;
253 newtag->lockfuncarg = NULL;
254 }
255 newtag->segments = NULL;
256
257 /* Take into account any restrictions imposed by our parent tag */
258 if (parent != NULL) {
259 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
260 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
261 if (newtag->boundary == 0)
262 newtag->boundary = parent->boundary;
263 else if (parent->boundary != 0)
264 newtag->boundary = MIN(parent->boundary,
265 newtag->boundary);
266 if (newtag->filter == NULL) {
267 /*
268 * Short circuit looking at our parent directly
269 * since we have encapsulated all of its information
270 */
271 newtag->filter = parent->filter;
272 newtag->filterarg = parent->filterarg;
273 newtag->parent = parent->parent;
274 }
275 if (newtag->parent != NULL)
276 atomic_add_int(&parent->ref_count, 1);
277 }
278
279 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
280 || newtag->alignment > 1)
281 newtag->flags |= BUS_DMA_COULD_BOUNCE;
282
283 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
284 (flags & BUS_DMA_ALLOCNOW) != 0) {
285 struct bounce_zone *bz;
286
287 /* Must bounce */
288
289 if ((error = alloc_bounce_zone(newtag)) != 0) {
290 free(newtag, M_DEVBUF);
291 return (error);
292 }
293 bz = newtag->bounce_zone;
294
295 if (ptoa(bz->total_bpages) < maxsize) {
296 int pages;
297
298 pages = atop(maxsize) - bz->total_bpages;
299
300 /* Add pages to our bounce pool */
301 if (alloc_bounce_pages(newtag, pages) < pages)
302 error = ENOMEM;
303 }
304 /* Performed initial allocation */
305 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
306 }
307
308 if (error != 0) {
309 free(newtag, M_DEVBUF);
310 } else {
311 *dmat = newtag;
312 }
313 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
314 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
315 return (error);
316 }
317
318 int
319 bus_dma_tag_destroy(bus_dma_tag_t dmat)
320 {
321 bus_dma_tag_t dmat_copy;
322 int error;
323
324 error = 0;
325 dmat_copy = dmat;
326
327 if (dmat != NULL) {
328
329 if (dmat->map_count != 0) {
330 error = EBUSY;
331 goto out;
332 }
333
334 while (dmat != NULL) {
335 bus_dma_tag_t parent;
336
337 parent = dmat->parent;
338 atomic_subtract_int(&dmat->ref_count, 1);
339 if (dmat->ref_count == 0) {
340 if (dmat->segments != NULL)
341 free(dmat->segments, M_DEVBUF);
342 free(dmat, M_DEVBUF);
343 /*
344 * Last reference count, so
345 * release our reference
346 * count on our parent.
347 */
348 dmat = parent;
349 } else
350 dmat = NULL;
351 }
352 }
353 out:
354 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
355 return (error);
356 }
357
358 /*
359 * Allocate a handle for mapping from kva/uva/physical
360 * address space into bus device space.
361 */
362 int
363 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
364 {
365 int error;
366
367 error = 0;
368
369 if (dmat->segments == NULL) {
370 dmat->segments = (bus_dma_segment_t *)malloc(
371 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
372 M_NOWAIT);
373 if (dmat->segments == NULL) {
374 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
375 __func__, dmat, ENOMEM);
376 return (ENOMEM);
377 }
378 }
379
380 /*
381 * Bouncing might be required if the driver asks for an active
382 * exclusion region, a data alignment that is stricter than 1, and/or
383 * an active address boundary.
384 */
385 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
386
387 /* Must bounce */
388 struct bounce_zone *bz;
389 int maxpages;
390
391 if (dmat->bounce_zone == NULL) {
392 if ((error = alloc_bounce_zone(dmat)) != 0)
393 return (error);
394 }
395 bz = dmat->bounce_zone;
396
397 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
398 M_NOWAIT | M_ZERO);
399 if (*mapp == NULL) {
400 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
401 __func__, dmat, ENOMEM);
402 return (ENOMEM);
403 }
404
405 /* Initialize the new map */
406 STAILQ_INIT(&((*mapp)->bpages));
407
408 /*
409 * Attempt to add pages to our pool on a per-instance
410 * basis up to a sane limit.
411 */
412 if (dmat->alignment > 1)
413 maxpages = MAX_BPAGES;
414 else
415 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
416 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
417 || (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
418 int pages;
419
420 pages = MAX(atop(dmat->maxsize), 1);
421 pages = MIN(maxpages - bz->total_bpages, pages);
422 pages = MAX(pages, 1);
423 if (alloc_bounce_pages(dmat, pages) < pages)
424 error = ENOMEM;
425
426 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
427 if (error == 0)
428 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
429 } else {
430 error = 0;
431 }
432 }
433 } else {
434 *mapp = NULL;
435 }
436 if (error == 0)
437 dmat->map_count++;
438 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
439 __func__, dmat, dmat->flags, error);
440 return (error);
441 }
442
443 /*
444 * Destroy a handle for mapping from kva/uva/physical
445 * address space into bus device space.
446 */
447 int
448 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
449 {
450 if (map != NULL && map != &nobounce_dmamap) {
451 if (STAILQ_FIRST(&map->bpages) != NULL) {
452 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
453 __func__, dmat, EBUSY);
454 return (EBUSY);
455 }
456 free(map, M_DEVBUF);
457 }
458 dmat->map_count--;
459 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
460 return (0);
461 }
462
463
464 /*
465 * Allocate a piece of memory that can be efficiently mapped into
466 * bus device space based on the constraints lited in the dma tag.
467 * A dmamap to for use with dmamap_load is also allocated.
468 */
469 int
470 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
471 bus_dmamap_t *mapp)
472 {
473 int mflags;
474
475 if (flags & BUS_DMA_NOWAIT)
476 mflags = M_NOWAIT;
477 else
478 mflags = M_WAITOK;
479 if (flags & BUS_DMA_ZERO)
480 mflags |= M_ZERO;
481
482 /* If we succeed, no mapping/bouncing will be required */
483 *mapp = NULL;
484
485 if (dmat->segments == NULL) {
486 dmat->segments = (bus_dma_segment_t *)malloc(
487 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
488 M_NOWAIT);
489 if (dmat->segments == NULL) {
490 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
491 __func__, dmat, dmat->flags, ENOMEM);
492 return (ENOMEM);
493 }
494 }
495
496 /*
497 * XXX:
498 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
499 * alignment guarantees of malloc need to be nailed down, and the
500 * code below should be rewritten to take that into account.
501 *
502 * In the meantime, we'll warn the user if malloc gets it wrong.
503 */
504 if ((dmat->maxsize <= PAGE_SIZE) &&
505 (dmat->alignment < dmat->maxsize) &&
506 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
507 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
508 } else {
509 /*
510 * XXX Use Contigmalloc until it is merged into this facility
511 * and handles multi-seg allocations. Nobody is doing
512 * multi-seg allocations yet though.
513 * XXX Certain AGP hardware does.
514 */
515 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
516 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
517 dmat->boundary);
518 }
519 if (*vaddr == NULL) {
520 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
521 __func__, dmat, dmat->flags, ENOMEM);
522 return (ENOMEM);
523 } else if ((uintptr_t)*vaddr & (dmat->alignment - 1)) {
524 printf("bus_dmamem_alloc failed to align memory properly.\n");
525 }
526 if (flags & BUS_DMA_NOCACHE)
527 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
528 PAT_UNCACHEABLE);
529 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
530 __func__, dmat, dmat->flags, ENOMEM);
531 return (0);
532 }
533
534 /*
535 * Free a piece of memory and it's allociated dmamap, that was allocated
536 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
537 */
538 void
539 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
540 {
541 /*
542 * dmamem does not need to be bounced, so the map should be
543 * NULL
544 */
545 if (map != NULL)
546 panic("bus_dmamem_free: Invalid map freed\n");
547 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
548 if ((dmat->maxsize <= PAGE_SIZE) &&
549 (dmat->alignment < dmat->maxsize) &&
550 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
551 free(vaddr, M_DEVBUF);
552 else {
553 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
554 }
555 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
556 }
557
558 /*
559 * Utility function to load a linear buffer. lastaddrp holds state
560 * between invocations (for multiple-buffer loads). segp contains
561 * the starting segment on entrace, and the ending segment on exit.
562 * first indicates if this is the first invocation of this function.
563 */
564 static __inline int
565 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
566 bus_dmamap_t map,
567 void *buf, bus_size_t buflen,
568 pmap_t pmap,
569 int flags,
570 bus_addr_t *lastaddrp,
571 bus_dma_segment_t *segs,
572 int *segp,
573 int first)
574 {
575 bus_size_t sgsize;
576 bus_addr_t curaddr, lastaddr, baddr, bmask;
577 vm_offset_t vaddr;
578 bus_addr_t paddr;
579 int seg;
580
581 if (map == NULL)
582 map = &nobounce_dmamap;
583
584 if ((map != &nobounce_dmamap && map->pagesneeded == 0)
585 && ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0)) {
586 vm_offset_t vendaddr;
587
588 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
589 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
590 dmat->boundary, dmat->alignment);
591 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
592 map, &nobounce_dmamap, map->pagesneeded);
593 /*
594 * Count the number of bounce pages
595 * needed in order to complete this transfer
596 */
597 vaddr = trunc_page((vm_offset_t)buf);
598 vendaddr = (vm_offset_t)buf + buflen;
599
600 while (vaddr < vendaddr) {
601 paddr = pmap_kextract(vaddr);
602 if (run_filter(dmat, paddr) != 0)
603 map->pagesneeded++;
604 vaddr += PAGE_SIZE;
605 }
606 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
607 }
608
609 /* Reserve Necessary Bounce Pages */
610 if (map->pagesneeded != 0) {
611 mtx_lock(&bounce_lock);
612 if (flags & BUS_DMA_NOWAIT) {
613 if (reserve_bounce_pages(dmat, map, 0) != 0) {
614 mtx_unlock(&bounce_lock);
615 return (ENOMEM);
616 }
617 } else {
618 if (reserve_bounce_pages(dmat, map, 1) != 0) {
619 /* Queue us for resources */
620 map->dmat = dmat;
621 map->buf = buf;
622 map->buflen = buflen;
623 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
624 map, links);
625 mtx_unlock(&bounce_lock);
626 return (EINPROGRESS);
627 }
628 }
629 mtx_unlock(&bounce_lock);
630 }
631
632 vaddr = (vm_offset_t)buf;
633 lastaddr = *lastaddrp;
634 bmask = ~(dmat->boundary - 1);
635
636 for (seg = *segp; buflen > 0 ; ) {
637 /*
638 * Get the physical address for this segment.
639 */
640 if (pmap)
641 curaddr = pmap_extract(pmap, vaddr);
642 else
643 curaddr = pmap_kextract(vaddr);
644
645 /*
646 * Compute the segment size, and adjust counts.
647 */
648 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
649 if (buflen < sgsize)
650 sgsize = buflen;
651
652 /*
653 * Make sure we don't cross any boundaries.
654 */
655 if (dmat->boundary > 0) {
656 baddr = (curaddr + dmat->boundary) & bmask;
657 if (sgsize > (baddr - curaddr))
658 sgsize = (baddr - curaddr);
659 }
660
661 if (map->pagesneeded != 0 && run_filter(dmat, curaddr))
662 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
663
664 /*
665 * Insert chunk into a segment, coalescing with
666 * previous segment if possible.
667 */
668 if (first) {
669 segs[seg].ds_addr = curaddr;
670 segs[seg].ds_len = sgsize;
671 first = 0;
672 } else {
673 if (curaddr == lastaddr &&
674 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
675 (dmat->boundary == 0 ||
676 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
677 segs[seg].ds_len += sgsize;
678 else {
679 if (++seg >= dmat->nsegments)
680 break;
681 segs[seg].ds_addr = curaddr;
682 segs[seg].ds_len = sgsize;
683 }
684 }
685
686 lastaddr = curaddr + sgsize;
687 vaddr += sgsize;
688 buflen -= sgsize;
689 }
690
691 *segp = seg;
692 *lastaddrp = lastaddr;
693
694 /*
695 * Did we fit?
696 */
697 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
698 }
699
700 /*
701 * Map the buffer buf into bus space using the dmamap map.
702 */
703 int
704 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
705 bus_size_t buflen, bus_dmamap_callback_t *callback,
706 void *callback_arg, int flags)
707 {
708 bus_addr_t lastaddr = 0;
709 int error, nsegs = 0;
710
711 if (map != NULL) {
712 flags |= BUS_DMA_WAITOK;
713 map->callback = callback;
714 map->callback_arg = callback_arg;
715 }
716
717 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
718 &lastaddr, dmat->segments, &nsegs, 1);
719
720 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
721 __func__, dmat, dmat->flags, error, nsegs + 1);
722
723 if (error == EINPROGRESS) {
724 return (error);
725 }
726
727 if (error)
728 (*callback)(callback_arg, dmat->segments, 0, error);
729 else
730 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
731
732 /*
733 * Return ENOMEM to the caller so that it can pass it up the stack.
734 * This error only happens when NOWAIT is set, so deferal is disabled.
735 */
736 if (error == ENOMEM)
737 return (error);
738
739 return (0);
740 }
741
742
743 /*
744 * Like _bus_dmamap_load(), but for mbufs.
745 */
746 int
747 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
748 struct mbuf *m0,
749 bus_dmamap_callback2_t *callback, void *callback_arg,
750 int flags)
751 {
752 int nsegs, error;
753
754 M_ASSERTPKTHDR(m0);
755
756 flags |= BUS_DMA_NOWAIT;
757 nsegs = 0;
758 error = 0;
759 if (m0->m_pkthdr.len <= dmat->maxsize) {
760 int first = 1;
761 bus_addr_t lastaddr = 0;
762 struct mbuf *m;
763
764 for (m = m0; m != NULL && error == 0; m = m->m_next) {
765 if (m->m_len > 0) {
766 error = _bus_dmamap_load_buffer(dmat, map,
767 m->m_data, m->m_len,
768 NULL, flags, &lastaddr,
769 dmat->segments, &nsegs, first);
770 first = 0;
771 }
772 }
773 } else {
774 error = EINVAL;
775 }
776
777 if (error) {
778 /* force "no valid mappings" in callback */
779 (*callback)(callback_arg, dmat->segments, 0, 0, error);
780 } else {
781 (*callback)(callback_arg, dmat->segments,
782 nsegs+1, m0->m_pkthdr.len, error);
783 }
784 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
785 __func__, dmat, dmat->flags, error, nsegs + 1);
786 return (error);
787 }
788
789 int
790 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
791 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
792 int flags)
793 {
794 int error;
795
796 M_ASSERTPKTHDR(m0);
797
798 flags |= BUS_DMA_NOWAIT;
799 *nsegs = 0;
800 error = 0;
801 if (m0->m_pkthdr.len <= dmat->maxsize) {
802 int first = 1;
803 bus_addr_t lastaddr = 0;
804 struct mbuf *m;
805
806 for (m = m0; m != NULL && error == 0; m = m->m_next) {
807 if (m->m_len > 0) {
808 error = _bus_dmamap_load_buffer(dmat, map,
809 m->m_data, m->m_len,
810 NULL, flags, &lastaddr,
811 segs, nsegs, first);
812 first = 0;
813 }
814 }
815 } else {
816 error = EINVAL;
817 }
818
819 /* XXX FIXME: Having to increment nsegs is really annoying */
820 ++*nsegs;
821 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
822 __func__, dmat, dmat->flags, error, *nsegs);
823 return (error);
824 }
825
826 /*
827 * Like _bus_dmamap_load(), but for uios.
828 */
829 int
830 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
831 struct uio *uio,
832 bus_dmamap_callback2_t *callback, void *callback_arg,
833 int flags)
834 {
835 bus_addr_t lastaddr;
836 int nsegs, error, first, i;
837 bus_size_t resid;
838 struct iovec *iov;
839 pmap_t pmap;
840
841 flags |= BUS_DMA_NOWAIT;
842 resid = uio->uio_resid;
843 iov = uio->uio_iov;
844
845 if (uio->uio_segflg == UIO_USERSPACE) {
846 KASSERT(uio->uio_td != NULL,
847 ("bus_dmamap_load_uio: USERSPACE but no proc"));
848 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
849 } else
850 pmap = NULL;
851
852 nsegs = 0;
853 error = 0;
854 first = 1;
855 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
856 /*
857 * Now at the first iovec to load. Load each iovec
858 * until we have exhausted the residual count.
859 */
860 bus_size_t minlen =
861 resid < iov[i].iov_len ? resid : iov[i].iov_len;
862 caddr_t addr = (caddr_t) iov[i].iov_base;
863
864 if (minlen > 0) {
865 error = _bus_dmamap_load_buffer(dmat, map,
866 addr, minlen, pmap, flags, &lastaddr,
867 dmat->segments, &nsegs, first);
868 first = 0;
869
870 resid -= minlen;
871 }
872 }
873
874 if (error) {
875 /* force "no valid mappings" in callback */
876 (*callback)(callback_arg, dmat->segments, 0, 0, error);
877 } else {
878 (*callback)(callback_arg, dmat->segments,
879 nsegs+1, uio->uio_resid, error);
880 }
881 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
882 __func__, dmat, dmat->flags, error, nsegs + 1);
883 return (error);
884 }
885
886 /*
887 * Release the mapping held by map.
888 */
889 void
890 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
891 {
892 struct bounce_page *bpage;
893
894 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
895 STAILQ_REMOVE_HEAD(&map->bpages, links);
896 free_bounce_page(dmat, bpage);
897 }
898 }
899
900 void
901 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
902 {
903 struct bounce_page *bpage;
904
905 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
906 /*
907 * Handle data bouncing. We might also
908 * want to add support for invalidating
909 * the caches on broken hardware
910 */
911 dmat->bounce_zone->total_bounced++;
912 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
913 "performing bounce", __func__, op, dmat, dmat->flags);
914
915 if (op & BUS_DMASYNC_PREWRITE) {
916 while (bpage != NULL) {
917 bcopy((void *)bpage->datavaddr,
918 (void *)bpage->vaddr,
919 bpage->datacount);
920 bpage = STAILQ_NEXT(bpage, links);
921 }
922 }
923
924 if (op & BUS_DMASYNC_POSTREAD) {
925 while (bpage != NULL) {
926 bcopy((void *)bpage->vaddr,
927 (void *)bpage->datavaddr,
928 bpage->datacount);
929 bpage = STAILQ_NEXT(bpage, links);
930 }
931 }
932 }
933 }
934
935 static void
936 init_bounce_pages(void *dummy __unused)
937 {
938
939 total_bpages = 0;
940 STAILQ_INIT(&bounce_zone_list);
941 STAILQ_INIT(&bounce_map_waitinglist);
942 STAILQ_INIT(&bounce_map_callbacklist);
943 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
944 }
945 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
946
947 static struct sysctl_ctx_list *
948 busdma_sysctl_tree(struct bounce_zone *bz)
949 {
950 return (&bz->sysctl_tree);
951 }
952
953 static struct sysctl_oid *
954 busdma_sysctl_tree_top(struct bounce_zone *bz)
955 {
956 return (bz->sysctl_tree_top);
957 }
958
959 static int
960 alloc_bounce_zone(bus_dma_tag_t dmat)
961 {
962 struct bounce_zone *bz;
963
964 /* Check to see if we already have a suitable zone */
965 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
966 if ((dmat->alignment <= bz->alignment)
967 && (dmat->boundary <= bz->boundary)
968 && (dmat->lowaddr >= bz->lowaddr)) {
969 dmat->bounce_zone = bz;
970 return (0);
971 }
972 }
973
974 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
975 M_NOWAIT | M_ZERO)) == NULL)
976 return (ENOMEM);
977
978 STAILQ_INIT(&bz->bounce_page_list);
979 bz->free_bpages = 0;
980 bz->reserved_bpages = 0;
981 bz->active_bpages = 0;
982 bz->lowaddr = dmat->lowaddr;
983 bz->alignment = dmat->alignment;
984 bz->boundary = dmat->boundary;
985 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
986 busdma_zonecount++;
987 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
988 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
989 dmat->bounce_zone = bz;
990
991 sysctl_ctx_init(&bz->sysctl_tree);
992 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
993 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
994 CTLFLAG_RD, 0, "");
995 if (bz->sysctl_tree_top == NULL) {
996 sysctl_ctx_free(&bz->sysctl_tree);
997 return (0); /* XXX error code? */
998 }
999
1000 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1001 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1002 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1003 "Total bounce pages");
1004 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1005 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1006 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1007 "Free bounce pages");
1008 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1009 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1010 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1011 "Reserved bounce pages");
1012 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1013 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1014 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1015 "Active bounce pages");
1016 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1017 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1018 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1019 "Total bounce requests");
1020 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1021 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1022 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1023 "Total bounce requests that were deferred");
1024 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1025 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1026 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1027 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1028 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1029 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1030 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1031 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1032 "boundary", CTLFLAG_RD, &bz->boundary, 0, "");
1033
1034 return (0);
1035 }
1036
1037 static int
1038 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1039 {
1040 struct bounce_zone *bz;
1041 int count;
1042
1043 bz = dmat->bounce_zone;
1044 count = 0;
1045 while (numpages > 0) {
1046 struct bounce_page *bpage;
1047
1048 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1049 M_NOWAIT | M_ZERO);
1050
1051 if (bpage == NULL)
1052 break;
1053 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1054 M_NOWAIT, 0ul,
1055 bz->lowaddr,
1056 PAGE_SIZE,
1057 bz->boundary);
1058 if (bpage->vaddr == 0) {
1059 free(bpage, M_DEVBUF);
1060 break;
1061 }
1062 bpage->busaddr = pmap_kextract(bpage->vaddr);
1063 mtx_lock(&bounce_lock);
1064 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1065 total_bpages++;
1066 bz->total_bpages++;
1067 bz->free_bpages++;
1068 mtx_unlock(&bounce_lock);
1069 count++;
1070 numpages--;
1071 }
1072 return (count);
1073 }
1074
1075 static int
1076 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1077 {
1078 struct bounce_zone *bz;
1079 int pages;
1080
1081 mtx_assert(&bounce_lock, MA_OWNED);
1082 bz = dmat->bounce_zone;
1083 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1084 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1085 return (map->pagesneeded - (map->pagesreserved + pages));
1086 bz->free_bpages -= pages;
1087 bz->reserved_bpages += pages;
1088 map->pagesreserved += pages;
1089 pages = map->pagesneeded - map->pagesreserved;
1090
1091 return (pages);
1092 }
1093
1094 static bus_addr_t
1095 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1096 bus_size_t size)
1097 {
1098 struct bounce_zone *bz;
1099 struct bounce_page *bpage;
1100
1101 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1102 KASSERT(map != NULL && map != &nobounce_dmamap,
1103 ("add_bounce_page: bad map %p", map));
1104
1105 bz = dmat->bounce_zone;
1106 if (map->pagesneeded == 0)
1107 panic("add_bounce_page: map doesn't need any pages");
1108 map->pagesneeded--;
1109
1110 if (map->pagesreserved == 0)
1111 panic("add_bounce_page: map doesn't need any pages");
1112 map->pagesreserved--;
1113
1114 mtx_lock(&bounce_lock);
1115 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1116 if (bpage == NULL)
1117 panic("add_bounce_page: free page list is empty");
1118
1119 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1120 bz->reserved_bpages--;
1121 bz->active_bpages++;
1122 mtx_unlock(&bounce_lock);
1123
1124 bpage->datavaddr = vaddr;
1125 bpage->datacount = size;
1126 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1127 return (bpage->busaddr);
1128 }
1129
1130 static void
1131 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1132 {
1133 struct bus_dmamap *map;
1134 struct bounce_zone *bz;
1135
1136 bz = dmat->bounce_zone;
1137 bpage->datavaddr = 0;
1138 bpage->datacount = 0;
1139
1140 mtx_lock(&bounce_lock);
1141 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1142 bz->free_bpages++;
1143 bz->active_bpages--;
1144 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1145 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1146 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1147 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1148 map, links);
1149 busdma_swi_pending = 1;
1150 bz->total_deferred++;
1151 swi_sched(vm_ih, 0);
1152 }
1153 }
1154 mtx_unlock(&bounce_lock);
1155 }
1156
1157 void
1158 busdma_swi(void)
1159 {
1160 bus_dma_tag_t dmat;
1161 struct bus_dmamap *map;
1162
1163 mtx_lock(&bounce_lock);
1164 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1165 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1166 mtx_unlock(&bounce_lock);
1167 dmat = map->dmat;
1168 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1169 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1170 map->callback, map->callback_arg, /*flags*/0);
1171 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1172 mtx_lock(&bounce_lock);
1173 }
1174 mtx_unlock(&bounce_lock);
1175 }
Cache object: d27004636dfc1a7ea80a033ab7e93d01
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