kernel tree reorganization stage 1: Major cvs repository work (not logged as
[dragonfly.git] / sys / i386 / i386 / busdma_machdep.c
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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 * $FreeBSD: src/sys/i386/i386/busdma_machdep.c,v 1.16.2.2 2003/01/23 00:55:27 scottl Exp $
93eb6220 27 * $DragonFly: src/sys/i386/i386/Attic/busdma_machdep.c,v 1.4 2003/07/27 01:49:51 hmp Exp $
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28 */
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/malloc.h>
33#include <sys/mbuf.h>
34#include <sys/uio.h>
35
36#include <vm/vm.h>
37#include <vm/vm_page.h>
38
39/* XXX needed for to access pmap to convert per-proc virtual to physical */
40#include <sys/proc.h>
41#include <sys/lock.h>
42#include <vm/vm_map.h>
43
44#include <machine/bus.h>
45#include <machine/md_var.h>
46
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47#define MAX_BPAGES 128
48
49struct bus_dma_tag {
50 bus_dma_tag_t parent;
51 bus_size_t alignment;
52 bus_size_t boundary;
53 bus_addr_t lowaddr;
54 bus_addr_t highaddr;
55 bus_dma_filter_t *filter;
56 void *filterarg;
57 bus_size_t maxsize;
58 u_int nsegments;
59 bus_size_t maxsegsz;
60 int flags;
61 int ref_count;
62 int map_count;
63};
64
65struct bounce_page {
66 vm_offset_t vaddr; /* kva of bounce buffer */
67 bus_addr_t busaddr; /* Physical address */
68 vm_offset_t datavaddr; /* kva of client data */
69 bus_size_t datacount; /* client data count */
70 STAILQ_ENTRY(bounce_page) links;
71};
72
73int busdma_swi_pending;
74
75static STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
76static int free_bpages;
77static int reserved_bpages;
78static int active_bpages;
79static int total_bpages;
80static bus_addr_t bounce_lowaddr = BUS_SPACE_MAXADDR;
81
82struct bus_dmamap {
83 struct bp_list bpages;
84 int pagesneeded;
85 int pagesreserved;
86 bus_dma_tag_t dmat;
87 void *buf; /* unmapped buffer pointer */
88 bus_size_t buflen; /* unmapped buffer length */
89 bus_dmamap_callback_t *callback;
90 void *callback_arg;
91 STAILQ_ENTRY(bus_dmamap) links;
92};
93
94static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
95static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
96static struct bus_dmamap nobounce_dmamap;
97
98static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
99static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map);
100static vm_offset_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
101 vm_offset_t vaddr, bus_size_t size);
102static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
103static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
104
105static __inline int
106run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
107{
108 int retval;
109
110 retval = 0;
111 do {
112 if (paddr > dmat->lowaddr
113 && paddr <= dmat->highaddr
114 && (dmat->filter == NULL
115 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
116 retval = 1;
117
118 dmat = dmat->parent;
119 } while (retval == 0 && dmat != NULL);
120 return (retval);
121}
122
123#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
124/*
125 * Allocate a device specific dma_tag.
126 */
127int
128bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
129 bus_size_t boundary, bus_addr_t lowaddr,
130 bus_addr_t highaddr, bus_dma_filter_t *filter,
131 void *filterarg, bus_size_t maxsize, int nsegments,
132 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
133{
134 bus_dma_tag_t newtag;
135 int error = 0;
136
137 /* Return a NULL tag on failure */
138 *dmat = NULL;
139
140 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, M_NOWAIT);
141 if (newtag == NULL)
142 return (ENOMEM);
143
144 newtag->parent = parent;
145 newtag->alignment = alignment;
146 newtag->boundary = boundary;
147 newtag->lowaddr = trunc_page((vm_offset_t)lowaddr) + (PAGE_SIZE - 1);
148 newtag->highaddr = trunc_page((vm_offset_t)highaddr) + (PAGE_SIZE - 1);
149 newtag->filter = filter;
150 newtag->filterarg = filterarg;
151 newtag->maxsize = maxsize;
152 newtag->nsegments = nsegments;
153 newtag->maxsegsz = maxsegsz;
154 newtag->flags = flags;
155 newtag->ref_count = 1; /* Count ourself */
156 newtag->map_count = 0;
157
158 /* Take into account any restrictions imposed by our parent tag */
159 if (parent != NULL) {
160 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
161 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
162 /*
163 * XXX Not really correct??? Probably need to honor boundary
164 * all the way up the inheritence chain.
165 */
166 newtag->boundary = MAX(parent->boundary, newtag->boundary);
167 if (newtag->filter == NULL) {
168 /*
169 * Short circuit looking at our parent directly
170 * since we have encapsulated all of its information
171 */
172 newtag->filter = parent->filter;
173 newtag->filterarg = parent->filterarg;
174 newtag->parent = parent->parent;
175 }
176 if (newtag->parent != NULL) {
177 parent->ref_count++;
178 }
179 }
180
181 if (newtag->lowaddr < ptoa(Maxmem) && (flags & BUS_DMA_ALLOCNOW) != 0) {
182 /* Must bounce */
183
184 if (lowaddr > bounce_lowaddr) {
185 /*
186 * Go through the pool and kill any pages
187 * that don't reside below lowaddr.
188 */
189 panic("bus_dma_tag_create: page reallocation "
190 "not implemented");
191 }
192 if (ptoa(total_bpages) < maxsize) {
193 int pages;
194
195 pages = atop(maxsize) - total_bpages;
196
197 /* Add pages to our bounce pool */
198 if (alloc_bounce_pages(newtag, pages) < pages)
199 error = ENOMEM;
200 }
201 /* Performed initial allocation */
202 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
203 }
204
205 if (error != 0) {
206 free(newtag, M_DEVBUF);
207 } else {
208 *dmat = newtag;
209 }
210 return (error);
211}
212
213int
214bus_dma_tag_destroy(bus_dma_tag_t dmat)
215{
216 if (dmat != NULL) {
217
218 if (dmat->map_count != 0)
219 return (EBUSY);
220
221 while (dmat != NULL) {
222 bus_dma_tag_t parent;
223
224 parent = dmat->parent;
225 dmat->ref_count--;
226 if (dmat->ref_count == 0) {
227 free(dmat, M_DEVBUF);
228 /*
229 * Last reference count, so
230 * release our reference
231 * count on our parent.
232 */
233 dmat = parent;
234 } else
235 dmat = NULL;
236 }
237 }
238 return (0);
239}
240
241/*
242 * Allocate a handle for mapping from kva/uva/physical
243 * address space into bus device space.
244 */
245int
246bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
247{
248 int error;
249
250 error = 0;
251
252 if (dmat->lowaddr < ptoa(Maxmem)) {
253 /* Must bounce */
254 int maxpages;
255
256 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
257 M_NOWAIT);
258 if (*mapp == NULL) {
259 return (ENOMEM);
260 } else {
261 /* Initialize the new map */
262 bzero(*mapp, sizeof(**mapp));
263 STAILQ_INIT(&((*mapp)->bpages));
264 }
265 /*
266 * Attempt to add pages to our pool on a per-instance
267 * basis up to a sane limit.
268 */
269 maxpages = MIN(MAX_BPAGES, Maxmem - atop(dmat->lowaddr));
270 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
271 || (dmat->map_count > 0
272 && total_bpages < maxpages)) {
273 int pages;
274
275 if (dmat->lowaddr > bounce_lowaddr) {
276 /*
277 * Go through the pool and kill any pages
278 * that don't reside below lowaddr.
279 */
280 panic("bus_dmamap_create: page reallocation "
281 "not implemented");
282 }
283 pages = atop(dmat->maxsize);
284 pages = MIN(maxpages - total_bpages, pages);
285 error = alloc_bounce_pages(dmat, pages);
286
287 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
288 if (error == 0)
289 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
290 } else {
291 error = 0;
292 }
293 }
294 } else {
295 *mapp = NULL;
296 }
297 if (error == 0)
298 dmat->map_count++;
299 return (error);
300}
301
302/*
303 * Destroy a handle for mapping from kva/uva/physical
304 * address space into bus device space.
305 */
306int
307bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
308{
309 if (map != NULL) {
310 if (STAILQ_FIRST(&map->bpages) != NULL)
311 return (EBUSY);
312 free(map, M_DEVBUF);
313 }
314 dmat->map_count--;
315 return (0);
316}
317
318
319/*
320 * Allocate a piece of memory that can be efficiently mapped into
321 * bus device space based on the constraints lited in the dma tag.
322 * A dmamap to for use with dmamap_load is also allocated.
323 */
324int
325bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
326 bus_dmamap_t *mapp)
327{
328 /* If we succeed, no mapping/bouncing will be required */
329 *mapp = NULL;
330
331 if ((dmat->maxsize <= PAGE_SIZE) && dmat->lowaddr >= ptoa(Maxmem)) {
332 *vaddr = malloc(dmat->maxsize, M_DEVBUF,
333 (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK);
334 } else {
335 /*
336 * XXX Use Contigmalloc until it is merged into this facility
337 * and handles multi-seg allocations. Nobody is doing
338 * multi-seg allocations yet though.
339 */
340 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF,
341 (flags & BUS_DMA_NOWAIT) ? M_NOWAIT : M_WAITOK,
342 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
343 dmat->boundary);
344 }
345 if (*vaddr == NULL)
346 return (ENOMEM);
347 return (0);
348}
349
350/*
351 * Free a piece of memory and it's allociated dmamap, that was allocated
352 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
353 */
354void
355bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
356{
357 /*
358 * dmamem does not need to be bounced, so the map should be
359 * NULL
360 */
361 if (map != NULL)
362 panic("bus_dmamem_free: Invalid map freed\n");
363 if ((dmat->maxsize <= PAGE_SIZE) && dmat->lowaddr >= ptoa(Maxmem))
364 free(vaddr, M_DEVBUF);
365 else
366 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
367}
368
369#define BUS_DMAMAP_NSEGS ((BUS_SPACE_MAXSIZE / PAGE_SIZE) + 1)
370
371/*
372 * Map the buffer buf into bus space using the dmamap map.
373 */
374int
375bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
376 bus_size_t buflen, bus_dmamap_callback_t *callback,
377 void *callback_arg, int flags)
378{
379 vm_offset_t vaddr;
380 vm_offset_t paddr;
381#ifdef __GNUC__
382 bus_dma_segment_t dm_segments[dmat->nsegments];
383#else
384 bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
385#endif
386 bus_dma_segment_t *sg;
387 int seg;
388 int error;
389 vm_offset_t nextpaddr;
390
391 if (map == NULL)
392 map = &nobounce_dmamap;
393
394 error = 0;
395 /*
396 * If we are being called during a callback, pagesneeded will
397 * be non-zero, so we can avoid doing the work twice.
398 */
399 if (dmat->lowaddr < ptoa(Maxmem) && map->pagesneeded == 0) {
400 vm_offset_t vendaddr;
401
402 /*
403 * Count the number of bounce pages
404 * needed in order to complete this transfer
405 */
406 vaddr = trunc_page((vm_offset_t)buf);
407 vendaddr = (vm_offset_t)buf + buflen;
408
409 while (vaddr < vendaddr) {
410 paddr = pmap_kextract(vaddr);
411 if (run_filter(dmat, paddr) != 0) {
412
413 map->pagesneeded++;
414 }
415 vaddr += PAGE_SIZE;
416 }
417 }
418
419 /* Reserve Necessary Bounce Pages */
420 if (map->pagesneeded != 0) {
421 int s;
422
423 s = splhigh();
424 if (reserve_bounce_pages(dmat, map) != 0) {
425
426 /* Queue us for resources */
427 map->dmat = dmat;
428 map->buf = buf;
429 map->buflen = buflen;
430 map->callback = callback;
431 map->callback_arg = callback_arg;
432
433 STAILQ_INSERT_TAIL(&bounce_map_waitinglist, map, links);
434 splx(s);
435
436 return (EINPROGRESS);
437 }
438 splx(s);
439 }
440
441 vaddr = (vm_offset_t)buf;
442 sg = &dm_segments[0];
443 seg = 1;
444 sg->ds_len = 0;
445
446 nextpaddr = 0;
447 do {
448 bus_size_t size;
449
450 paddr = pmap_kextract(vaddr);
451 size = PAGE_SIZE - (paddr & PAGE_MASK);
452 if (size > buflen)
453 size = buflen;
454
455 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
456 paddr = add_bounce_page(dmat, map, vaddr, size);
457 }
458
459 if (sg->ds_len == 0) {
460 sg->ds_addr = paddr;
461 sg->ds_len = size;
462 } else if (paddr == nextpaddr) {
463 sg->ds_len += size;
464 } else {
465 /* Go to the next segment */
466 sg++;
467 seg++;
468 if (seg > dmat->nsegments)
469 break;
470 sg->ds_addr = paddr;
471 sg->ds_len = size;
472 }
473 vaddr += size;
474 nextpaddr = paddr + size;
475 buflen -= size;
476
477 } while (buflen > 0);
478
479 if (buflen != 0) {
480 printf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",
481 (u_long)buflen);
482 error = EFBIG;
483 }
484
485 (*callback)(callback_arg, dm_segments, seg, error);
486
487 return (0);
488}
489
490/*
491 * Utility function to load a linear buffer. lastaddrp holds state
492 * between invocations (for multiple-buffer loads). segp contains
493 * the starting segment on entrace, and the ending segment on exit.
494 * first indicates if this is the first invocation of this function.
495 */
496static int
497_bus_dmamap_load_buffer(bus_dma_tag_t dmat,
498 bus_dma_segment_t segs[],
499 void *buf, bus_size_t buflen,
dadab5e9 500 struct thread *td,
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501 int flags,
502 vm_offset_t *lastaddrp,
503 int *segp,
504 int first)
505{
506 bus_size_t sgsize;
507 bus_addr_t curaddr, lastaddr, baddr, bmask;
508 vm_offset_t vaddr = (vm_offset_t)buf;
509 int seg;
510 pmap_t pmap;
511
dadab5e9
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512 if (td->td_proc != NULL)
513 pmap = vmspace_pmap(td->td_proc->p_vmspace);
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514 else
515 pmap = NULL;
516
517 lastaddr = *lastaddrp;
518 bmask = ~(dmat->boundary - 1);
519
520 for (seg = *segp; buflen > 0 ; ) {
521 /*
522 * Get the physical address for this segment.
523 */
524 if (pmap)
525 curaddr = pmap_extract(pmap, vaddr);
526 else
527 curaddr = pmap_kextract(vaddr);
528
529 /*
530 * Compute the segment size, and adjust counts.
531 */
532 sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
533 if (buflen < sgsize)
534 sgsize = buflen;
535
536 /*
537 * Make sure we don't cross any boundaries.
538 */
539 if (dmat->boundary > 0) {
540 baddr = (curaddr + dmat->boundary) & bmask;
541 if (sgsize > (baddr - curaddr))
542 sgsize = (baddr - curaddr);
543 }
544
545 /*
546 * Insert chunk into a segment, coalescing with
547 * previous segment if possible.
548 */
549 if (first) {
550 segs[seg].ds_addr = curaddr;
551 segs[seg].ds_len = sgsize;
552 first = 0;
553 } else {
554 if (curaddr == lastaddr &&
555 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
556 (dmat->boundary == 0 ||
557 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
558 segs[seg].ds_len += sgsize;
559 else {
560 if (++seg >= dmat->nsegments)
561 break;
562 segs[seg].ds_addr = curaddr;
563 segs[seg].ds_len = sgsize;
564 }
565 }
566
567 lastaddr = curaddr + sgsize;
568 vaddr += sgsize;
569 buflen -= sgsize;
570 }
571
572 *segp = seg;
573 *lastaddrp = lastaddr;
574
575 /*
576 * Did we fit?
577 */
578 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
579}
580
581/*
582 * Like _bus_dmamap_load(), but for mbufs.
583 */
584int
585bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
586 struct mbuf *m0,
587 bus_dmamap_callback2_t *callback, void *callback_arg,
588 int flags)
589{
590#ifdef __GNUC__
591 bus_dma_segment_t dm_segments[dmat->nsegments];
592#else
593 bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
594#endif
595 int nsegs, error;
596
597 KASSERT(dmat->lowaddr >= ptoa(Maxmem) || map != NULL,
598 ("bus_dmamap_load_mbuf: No support for bounce pages!"));
599 KASSERT(m0->m_flags & M_PKTHDR,
600 ("bus_dmamap_load_mbuf: no packet header"));
601
602 nsegs = 0;
603 error = 0;
604 if (m0->m_pkthdr.len <= dmat->maxsize) {
605 int first = 1;
606 vm_offset_t lastaddr = 0;
607 struct mbuf *m;
608
609 for (m = m0; m != NULL && error == 0; m = m->m_next) {
610 error = _bus_dmamap_load_buffer(dmat,
611 dm_segments,
612 m->m_data, m->m_len,
613 NULL, flags, &lastaddr, &nsegs, first);
614 first = 0;
615 }
616 } else {
617 error = EINVAL;
618 }
619
620 if (error) {
621 /* force "no valid mappings" in callback */
622 (*callback)(callback_arg, dm_segments, 0, 0, error);
623 } else {
624 (*callback)(callback_arg, dm_segments,
625 nsegs+1, m0->m_pkthdr.len, error);
626 }
627 return (error);
628}
629
630/*
631 * Like _bus_dmamap_load(), but for uios.
632 */
633int
634bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
635 struct uio *uio,
636 bus_dmamap_callback2_t *callback, void *callback_arg,
637 int flags)
638{
639 vm_offset_t lastaddr;
640#ifdef __GNUC__
641 bus_dma_segment_t dm_segments[dmat->nsegments];
642#else
643 bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
644#endif
645 int nsegs, error, first, i;
646 bus_size_t resid;
647 struct iovec *iov;
dadab5e9 648 struct thread *td = NULL;
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649
650 KASSERT(dmat->lowaddr >= ptoa(Maxmem) || map != NULL,
651 ("bus_dmamap_load_uio: No support for bounce pages!"));
652
653 resid = uio->uio_resid;
654 iov = uio->uio_iov;
655
656 if (uio->uio_segflg == UIO_USERSPACE) {
dadab5e9
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657 td = uio->uio_td;
658 KASSERT(td != NULL && td->td_proc != NULL,
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659 ("bus_dmamap_load_uio: USERSPACE but no proc"));
660 }
661
662 nsegs = 0;
663 error = 0;
664 first = 1;
665 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
666 /*
667 * Now at the first iovec to load. Load each iovec
668 * until we have exhausted the residual count.
669 */
670 bus_size_t minlen =
671 resid < iov[i].iov_len ? resid : iov[i].iov_len;
672 caddr_t addr = (caddr_t) iov[i].iov_base;
673
674 error = _bus_dmamap_load_buffer(dmat,
675 dm_segments,
676 addr, minlen,
dadab5e9 677 td, flags, &lastaddr, &nsegs, first);
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678 first = 0;
679
680 resid -= minlen;
681 }
682
683 if (error) {
684 /* force "no valid mappings" in callback */
685 (*callback)(callback_arg, dm_segments, 0, 0, error);
686 } else {
687 (*callback)(callback_arg, dm_segments,
688 nsegs+1, uio->uio_resid, error);
689 }
690 return (error);
691}
692
693/*
694 * Release the mapping held by map.
695 */
696void
697_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
698{
699 struct bounce_page *bpage;
700
701 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
702 STAILQ_REMOVE_HEAD(&map->bpages, links);
703 free_bounce_page(dmat, bpage);
704 }
705}
706
707void
708_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
709{
710 struct bounce_page *bpage;
711
712 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
713
714 /*
715 * Handle data bouncing. We might also
716 * want to add support for invalidating
717 * the caches on broken hardware
718 */
719 switch (op) {
720 case BUS_DMASYNC_PREWRITE:
721 while (bpage != NULL) {
722 bcopy((void *)bpage->datavaddr,
723 (void *)bpage->vaddr,
724 bpage->datacount);
725 bpage = STAILQ_NEXT(bpage, links);
726 }
727 break;
728
729 case BUS_DMASYNC_POSTREAD:
730 while (bpage != NULL) {
731 bcopy((void *)bpage->vaddr,
732 (void *)bpage->datavaddr,
733 bpage->datacount);
734 bpage = STAILQ_NEXT(bpage, links);
735 }
736 break;
737 case BUS_DMASYNC_PREREAD:
738 case BUS_DMASYNC_POSTWRITE:
739 /* No-ops */
740 break;
741 }
742 }
743}
744
745static int
746alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
747{
748 int count;
749
750 count = 0;
751 if (total_bpages == 0) {
752 STAILQ_INIT(&bounce_page_list);
753 STAILQ_INIT(&bounce_map_waitinglist);
754 STAILQ_INIT(&bounce_map_callbacklist);
755 }
756
757 while (numpages > 0) {
758 struct bounce_page *bpage;
759 int s;
760
761 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
762 M_NOWAIT);
763
764 if (bpage == NULL)
765 break;
766 bzero(bpage, sizeof(*bpage));
767 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
768 M_NOWAIT, 0ul,
769 dmat->lowaddr,
770 PAGE_SIZE,
771 0);
772 if (bpage->vaddr == NULL) {
773 free(bpage, M_DEVBUF);
774 break;
775 }
776 bpage->busaddr = pmap_kextract(bpage->vaddr);
777 s = splhigh();
778 STAILQ_INSERT_TAIL(&bounce_page_list, bpage, links);
779 total_bpages++;
780 free_bpages++;
781 splx(s);
782 count++;
783 numpages--;
784 }
785 return (count);
786}
787
788static int
789reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
790{
791 int pages;
792
793 pages = MIN(free_bpages, map->pagesneeded - map->pagesreserved);
794 free_bpages -= pages;
795 reserved_bpages += pages;
796 map->pagesreserved += pages;
797 pages = map->pagesneeded - map->pagesreserved;
798
799 return (pages);
800}
801
802static vm_offset_t
803add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
804 bus_size_t size)
805{
806 int s;
807 struct bounce_page *bpage;
808
809 if (map->pagesneeded == 0)
810 panic("add_bounce_page: map doesn't need any pages");
811 map->pagesneeded--;
812
813 if (map->pagesreserved == 0)
814 panic("add_bounce_page: map doesn't need any pages");
815 map->pagesreserved--;
816
817 s = splhigh();
818 bpage = STAILQ_FIRST(&bounce_page_list);
819 if (bpage == NULL)
820 panic("add_bounce_page: free page list is empty");
821
822 STAILQ_REMOVE_HEAD(&bounce_page_list, links);
823 reserved_bpages--;
824 active_bpages++;
825 splx(s);
826
827 bpage->datavaddr = vaddr;
828 bpage->datacount = size;
829 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
830 return (bpage->busaddr);
831}
832
833static void
834free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
835{
836 int s;
837 struct bus_dmamap *map;
838
839 bpage->datavaddr = 0;
840 bpage->datacount = 0;
841
842 s = splhigh();
843 STAILQ_INSERT_HEAD(&bounce_page_list, bpage, links);
844 free_bpages++;
845 active_bpages--;
846 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
847 if (reserve_bounce_pages(map->dmat, map) == 0) {
848 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
849 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
850 map, links);
851 busdma_swi_pending = 1;
852 setsoftvm();
853 }
854 }
855 splx(s);
856}
857
858void
859busdma_swi()
860{
861 int s;
862 struct bus_dmamap *map;
863
864 s = splhigh();
865 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
866 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
867 splx(s);
868 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
869 map->callback, map->callback_arg, /*flags*/0);
870 s = splhigh();
871 }
872 splx(s);
873}