bus_dma_tag fixes and enhancements.
[dragonfly.git] / sys / platform / pc64 / amd64 / busdma_machdep.c
CommitLineData
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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 *
20d01610
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26 * $FreeBSD: src/sys/i386/i386/busdma_machdep.c,v 1.94 2008/08/15 20:51:31 kmacy Exp $
27 * $DragonFly: src/sys/platform/pc32/i386/busdma_machdep.c,v 1.23 2008/06/05 18:06:32 swildner Exp $
d7f50089
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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#include <sys/thread2.h>
36#include <sys/bus_dma.h>
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37#include <sys/kernel.h>
38#include <sys/sysctl.h>
39#include <sys/lock.h>
40#include <sys/spinlock2.h>
d7f50089
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41
42#include <vm/vm.h>
43#include <vm/vm_page.h>
44
45/* XXX needed for to access pmap to convert per-proc virtual to physical */
46#include <sys/proc.h>
47#include <sys/lock.h>
48#include <vm/vm_map.h>
49
50#include <machine/md_var.h>
51
20d01610
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52#define MAX_BPAGES 1024
53
6eed46e7
MD
54/*
55 * 16 x N declared on stack.
56 */
57#define BUS_DMA_CACHE_SEGMENTS 8
58
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59struct bounce_zone;
60struct bus_dmamap;
d7f50089
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61
62struct bus_dma_tag {
20d01610
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63 bus_dma_tag_t parent;
64 bus_size_t alignment;
65 bus_size_t boundary;
66 bus_addr_t lowaddr;
67 bus_addr_t highaddr;
d7f50089 68 bus_dma_filter_t *filter;
20d01610
SZ
69 void *filterarg;
70 bus_size_t maxsize;
71 u_int nsegments;
72 bus_size_t maxsegsz;
73 int flags;
74 int ref_count;
75 int map_count;
d7f50089 76 bus_dma_segment_t *segments;
20d01610 77 struct bounce_zone *bounce_zone;
6eed46e7
MD
78#ifdef SMP
79 struct spinlock spin;
80#else
81 int unused0;
82#endif
d7f50089
YY
83};
84
20d01610
SZ
85/*
86 * bus_dma_tag private flags
87 */
88#define BUS_DMA_BOUNCE_ALIGN BUS_DMA_BUS2
89#define BUS_DMA_BOUNCE_LOWADDR BUS_DMA_BUS3
90#define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
91
92#define BUS_DMA_COULD_BOUNCE (BUS_DMA_BOUNCE_LOWADDR | BUS_DMA_BOUNCE_ALIGN)
93
94#define BUS_DMAMEM_KMALLOC(dmat) \
95 ((dmat)->maxsize <= PAGE_SIZE && \
96 (dmat)->alignment <= PAGE_SIZE && \
97 (dmat)->lowaddr >= ptoa(Maxmem))
98
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99struct bounce_page {
100 vm_offset_t vaddr; /* kva of bounce buffer */
101 bus_addr_t busaddr; /* Physical address */
102 vm_offset_t datavaddr; /* kva of client data */
103 bus_size_t datacount; /* client data count */
104 STAILQ_ENTRY(bounce_page) links;
105};
106
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107struct bounce_zone {
108 STAILQ_ENTRY(bounce_zone) links;
109 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
110 STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
111#ifdef SMP
112 struct spinlock spin;
113#else
114 int unused0;
115#endif
116 int total_bpages;
117 int free_bpages;
118 int reserved_bpages;
119 int active_bpages;
120 int total_bounced;
121 int total_deferred;
122 int reserve_failed;
123 bus_size_t alignment;
124 bus_addr_t lowaddr;
125 char zoneid[8];
126 char lowaddrid[20];
127 struct sysctl_ctx_list sysctl_ctx;
128 struct sysctl_oid *sysctl_tree;
129};
130
131#ifdef SMP
132#define BZ_LOCK(bz) spin_lock_wr(&(bz)->spin)
133#define BZ_UNLOCK(bz) spin_unlock_wr(&(bz)->spin)
134#else
135#define BZ_LOCK(bz) crit_enter()
136#define BZ_UNLOCK(bz) crit_exit()
137#endif
138
139static struct lwkt_token bounce_zone_tok =
140 LWKT_TOKEN_INITIALIZER(bounce_zone_tok);
141static int busdma_zonecount;
142static STAILQ_HEAD(, bounce_zone) bounce_zone_list =
143 STAILQ_HEAD_INITIALIZER(bounce_zone_list);
144
d7f50089 145int busdma_swi_pending;
20d01610
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146static int total_bounce_pages;
147static int max_bounce_pages = MAX_BPAGES;
148static int bounce_alignment = 1; /* XXX temporary */
d7f50089 149
20d01610
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150TUNABLE_INT("hw.busdma.max_bpages", &max_bounce_pages);
151TUNABLE_INT("hw.busdma.bounce_alignment", &bounce_alignment);
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152
153struct bus_dmamap {
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154 struct bp_list bpages;
155 int pagesneeded;
156 int pagesreserved;
157 bus_dma_tag_t dmat;
158 void *buf; /* unmapped buffer pointer */
159 bus_size_t buflen; /* unmapped buffer length */
d7f50089 160 bus_dmamap_callback_t *callback;
20d01610 161 void *callback_arg;
d7f50089
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162 STAILQ_ENTRY(bus_dmamap) links;
163};
164
20d01610
SZ
165static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist =
166 STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist);
167
d7f50089
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168static struct bus_dmamap nobounce_dmamap;
169
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170static int alloc_bounce_zone(bus_dma_tag_t);
171static int alloc_bounce_pages(bus_dma_tag_t, u_int, int);
172static int reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int);
173static void return_bounce_pages(bus_dma_tag_t, bus_dmamap_t);
174static bus_addr_t add_bounce_page(bus_dma_tag_t, bus_dmamap_t,
175 vm_offset_t, bus_size_t);
176static void free_bounce_page(bus_dma_tag_t, struct bounce_page *);
177
178static bus_dmamap_t get_map_waiting(bus_dma_tag_t);
179static void add_map_callback(bus_dmamap_t);
180
181SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
182SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages,
183 0, "Total bounce pages");
184SYSCTL_INT(_hw_busdma, OID_AUTO, max_bpages, CTLFLAG_RD, &max_bounce_pages,
185 0, "Max bounce pages per bounce zone");
186SYSCTL_INT(_hw_busdma, OID_AUTO, bounce_alignment, CTLFLAG_RD,
187 &bounce_alignment, 0, "Obey alignment constraint");
d7f50089
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188
189static __inline int
190run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
191{
192 int retval;
193
194 retval = 0;
195 do {
20d01610
SZ
196 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) ||
197 (bounce_alignment && (paddr & (dmat->alignment - 1)) != 0))
198 && (dmat->filter == NULL ||
199 dmat->filter(dmat->filterarg, paddr) != 0))
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200 retval = 1;
201
20d01610 202 dmat = dmat->parent;
d7f50089
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203 } while (retval == 0 && dmat != NULL);
204 return (retval);
205}
206
d7f50089
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207/*
208 * Allocate a device specific dma_tag.
209 */
210int
211bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
212 bus_size_t boundary, bus_addr_t lowaddr,
213 bus_addr_t highaddr, bus_dma_filter_t *filter,
214 void *filterarg, bus_size_t maxsize, int nsegments,
215 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
216{
217 bus_dma_tag_t newtag;
218 int error = 0;
219
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220 /*
221 * Sanity checks
222 */
223
224 if (alignment == 0)
225 alignment = 1;
226 if (alignment & (alignment - 1))
227 panic("alignment must be power of 2\n");
228
229 if (boundary != 0) {
230 if (boundary & (boundary - 1))
231 panic("boundary must be power of 2\n");
232 if (boundary < maxsegsz) {
233 kprintf("boundary < maxsegsz:\n");
5e6bd7dc 234 print_backtrace();
20d01610
SZ
235 maxsegsz = boundary;
236 }
237 }
238
d7f50089
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239 /* Return a NULL tag on failure */
240 *dmat = NULL;
241
6eed46e7 242 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT | M_ZERO);
d7f50089 243
6eed46e7 244 spin_init(&newtag->spin);
d7f50089
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245 newtag->parent = parent;
246 newtag->alignment = alignment;
247 newtag->boundary = boundary;
248 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
249 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
250 newtag->filter = filter;
251 newtag->filterarg = filterarg;
252 newtag->maxsize = maxsize;
253 newtag->nsegments = nsegments;
254 newtag->maxsegsz = maxsegsz;
255 newtag->flags = flags;
256 newtag->ref_count = 1; /* Count ourself */
257 newtag->map_count = 0;
258 newtag->segments = NULL;
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259 newtag->bounce_zone = NULL;
260
d7f50089
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261 /* Take into account any restrictions imposed by our parent tag */
262 if (parent != NULL) {
263 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
264 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
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265
266 if (newtag->boundary == 0) {
267 newtag->boundary = parent->boundary;
268 } else if (parent->boundary != 0) {
269 newtag->boundary = MIN(parent->boundary,
270 newtag->boundary);
271 }
272
273#ifdef notyet
274 newtag->alignment = MAX(parent->alignment, newtag->alignment);
275#endif
276
d7f50089
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277 if (newtag->filter == NULL) {
278 /*
279 * Short circuit looking at our parent directly
280 * since we have encapsulated all of its information
281 */
282 newtag->filter = parent->filter;
283 newtag->filterarg = parent->filterarg;
284 newtag->parent = parent->parent;
285 }
20d01610 286 if (newtag->parent != NULL)
d7f50089 287 parent->ref_count++;
d7f50089 288 }
20d01610
SZ
289
290 if (newtag->lowaddr < ptoa(Maxmem))
291 newtag->flags |= BUS_DMA_BOUNCE_LOWADDR;
292 if (bounce_alignment && newtag->alignment > 1 &&
293 !(newtag->flags & BUS_DMA_ALIGNED))
294 newtag->flags |= BUS_DMA_BOUNCE_ALIGN;
295
296 if ((newtag->flags & BUS_DMA_COULD_BOUNCE) &&
d7f50089 297 (flags & BUS_DMA_ALLOCNOW) != 0) {
20d01610
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298 struct bounce_zone *bz;
299
d7f50089
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300 /* Must bounce */
301
20d01610
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302 error = alloc_bounce_zone(newtag);
303 if (error)
304 goto back;
305 bz = newtag->bounce_zone;
306
307 if (ptoa(bz->total_bpages) < maxsize) {
d7f50089
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308 int pages;
309
20d01610
SZ
310 if (flags & BUS_DMA_ONEBPAGE) {
311 pages = 1;
312 } else {
313 pages = atop(round_page(maxsize)) -
314 bz->total_bpages;
315 pages = MAX(pages, 1);
316 }
d7f50089
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317
318 /* Add pages to our bounce pool */
20d01610 319 if (alloc_bounce_pages(newtag, pages, flags) < pages)
d7f50089 320 error = ENOMEM;
20d01610
SZ
321
322 /* Performed initial allocation */
323 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
d7f50089 324 }
d7f50089 325 }
20d01610
SZ
326back:
327 if (error)
d7f50089 328 kfree(newtag, M_DEVBUF);
20d01610 329 else
d7f50089 330 *dmat = newtag;
20d01610 331 return error;
d7f50089
YY
332}
333
334int
335bus_dma_tag_destroy(bus_dma_tag_t dmat)
336{
337 if (dmat != NULL) {
d7f50089
YY
338 if (dmat->map_count != 0)
339 return (EBUSY);
340
341 while (dmat != NULL) {
342 bus_dma_tag_t parent;
343
344 parent = dmat->parent;
345 dmat->ref_count--;
346 if (dmat->ref_count == 0) {
347 if (dmat->segments != NULL)
348 kfree(dmat->segments, M_DEVBUF);
349 kfree(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 return (0);
361}
362
6eed46e7
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363bus_size_t
364bus_dma_tag_getmaxsize(bus_dma_tag_t tag)
365{
366 return(tag->maxsize);
367}
368
d7f50089
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369/*
370 * Allocate a handle for mapping from kva/uva/physical
371 * address space into bus device space.
372 */
373int
374bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
375{
376 int error;
377
378 error = 0;
379
380 if (dmat->segments == NULL) {
381 KKASSERT(dmat->nsegments && dmat->nsegments < 16384);
382 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
383 dmat->nsegments, M_DEVBUF, M_INTWAIT);
384 }
385
20d01610
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386 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
387 struct bounce_zone *bz;
d7f50089
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388 int maxpages;
389
20d01610
SZ
390 /* Must bounce */
391
392 if (dmat->bounce_zone == NULL) {
393 error = alloc_bounce_zone(dmat);
394 if (error)
395 return error;
396 }
397 bz = dmat->bounce_zone;
398
e7b4468c 399 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO);
20d01610 400
e7b4468c
SW
401 /* Initialize the new map */
402 STAILQ_INIT(&((*mapp)->bpages));
20d01610 403
d7f50089
YY
404 /*
405 * Attempt to add pages to our pool on a per-instance
406 * basis up to a sane limit.
407 */
20d01610
SZ
408 if (dmat->flags & BUS_DMA_BOUNCE_ALIGN) {
409 maxpages = max_bounce_pages;
410 } else {
411 maxpages = MIN(max_bounce_pages,
412 Maxmem - atop(dmat->lowaddr));
413 }
d7f50089
YY
414 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
415 || (dmat->map_count > 0
20d01610 416 && bz->total_bpages < maxpages)) {
d7f50089
YY
417 int pages;
418
20d01610
SZ
419 if (flags & BUS_DMA_ONEBPAGE) {
420 pages = 1;
421 } else {
422 pages = atop(round_page(dmat->maxsize));
423 pages = MIN(maxpages - bz->total_bpages, pages);
424 pages = MAX(pages, 1);
d7f50089 425 }
20d01610
SZ
426 if (alloc_bounce_pages(dmat, pages, flags) < pages)
427 error = ENOMEM;
d7f50089
YY
428
429 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
20d01610 430 if (!error)
d7f50089
YY
431 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
432 } else {
433 error = 0;
434 }
435 }
436 } else {
437 *mapp = NULL;
438 }
20d01610 439 if (!error)
d7f50089 440 dmat->map_count++;
20d01610 441 return error;
d7f50089
YY
442}
443
444/*
445 * Destroy a handle for mapping from kva/uva/physical
446 * address space into bus device space.
447 */
448int
449bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
450{
451 if (map != NULL) {
452 if (STAILQ_FIRST(&map->bpages) != NULL)
453 return (EBUSY);
454 kfree(map, M_DEVBUF);
455 }
456 dmat->map_count--;
457 return (0);
458}
459
20d01610
SZ
460static __inline bus_size_t
461check_kmalloc(bus_dma_tag_t dmat, const void *vaddr0, int verify)
462{
463 bus_size_t maxsize = 0;
464 uintptr_t vaddr = (uintptr_t)vaddr0;
465
466 if ((vaddr ^ (vaddr + dmat->maxsize - 1)) & ~PAGE_MASK) {
467 kprintf("boundary check failed\n");
468 if (verify)
5e6bd7dc 469 print_backtrace(); /* XXX panic */
20d01610
SZ
470 maxsize = dmat->maxsize;
471 }
472 if (vaddr & (dmat->alignment - 1)) {
473 kprintf("alignment check failed\n");
474 if (verify)
5e6bd7dc 475 print_backtrace(); /* XXX panic */
20d01610
SZ
476 if (dmat->maxsize < dmat->alignment)
477 maxsize = dmat->alignment;
478 else
479 maxsize = dmat->maxsize;
480 }
481 return maxsize;
482}
d7f50089
YY
483
484/*
485 * Allocate a piece of memory that can be efficiently mapped into
486 * bus device space based on the constraints lited in the dma tag.
487 *
488 * mapp is degenerate. By definition this allocation should not require
489 * bounce buffers so do not allocate a dma map.
490 */
491int
20d01610 492bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags,
d7f50089
YY
493 bus_dmamap_t *mapp)
494{
495 int mflags;
20d01610 496
d7f50089
YY
497 /* If we succeed, no mapping/bouncing will be required */
498 *mapp = NULL;
499
500 if (dmat->segments == NULL) {
501 KKASSERT(dmat->nsegments < 16384);
502 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
503 dmat->nsegments, M_DEVBUF, M_INTWAIT);
504 }
505
506 if (flags & BUS_DMA_NOWAIT)
507 mflags = M_NOWAIT;
508 else
509 mflags = M_WAITOK;
510 if (flags & BUS_DMA_ZERO)
511 mflags |= M_ZERO;
512
20d01610
SZ
513 if (BUS_DMAMEM_KMALLOC(dmat)) {
514 bus_size_t maxsize;
515
d7f50089 516 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags);
20d01610 517
d7f50089 518 /*
20d01610
SZ
519 * XXX
520 * Check whether the allocation
521 * - crossed a page boundary
522 * - was not aligned
523 * Retry with power-of-2 alignment in the above cases.
d7f50089 524 */
20d01610
SZ
525 maxsize = check_kmalloc(dmat, *vaddr, 0);
526 if (maxsize) {
d7f50089 527 size_t size;
20d01610 528
d7f50089
YY
529 kfree(*vaddr, M_DEVBUF);
530 /* XXX check for overflow? */
20d01610 531 for (size = 1; size <= maxsize; size <<= 1)
d7f50089
YY
532 ;
533 *vaddr = kmalloc(size, M_DEVBUF, mflags);
20d01610 534 check_kmalloc(dmat, *vaddr, 1);
d7f50089
YY
535 }
536 } else {
537 /*
538 * XXX Use Contigmalloc until it is merged into this facility
539 * and handles multi-seg allocations. Nobody is doing
540 * multi-seg allocations yet though.
541 */
542 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
20d01610 543 0ul, dmat->lowaddr, dmat->alignment, dmat->boundary);
d7f50089
YY
544 }
545 if (*vaddr == NULL)
546 return (ENOMEM);
547 return (0);
548}
549
550/*
551 * Free a piece of memory and it's allociated dmamap, that was allocated
552 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
553 */
554void
555bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
556{
557 /*
558 * dmamem does not need to be bounced, so the map should be
559 * NULL
560 */
561 if (map != NULL)
562 panic("bus_dmamem_free: Invalid map freed\n");
20d01610 563 if (BUS_DMAMEM_KMALLOC(dmat))
d7f50089
YY
564 kfree(vaddr, M_DEVBUF);
565 else
566 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
567}
568
20d01610
SZ
569static __inline vm_paddr_t
570_bus_dma_extract(pmap_t pmap, vm_offset_t vaddr)
571{
572 if (pmap)
573 return pmap_extract(pmap, vaddr);
574 else
575 return pmap_kextract(vaddr);
576}
d7f50089
YY
577
578/*
20d01610
SZ
579 * Utility function to load a linear buffer. lastaddrp holds state
580 * between invocations (for multiple-buffer loads). segp contains
581 * the segment following the starting one on entrace, and the ending
582 * segment on exit. first indicates if this is the first invocation
583 * of this function.
d7f50089 584 */
20d01610
SZ
585static int
586_bus_dmamap_load_buffer(bus_dma_tag_t dmat,
587 bus_dmamap_t map,
588 void *buf, bus_size_t buflen,
589 bus_dma_segment_t *segments,
590 int nsegments,
591 pmap_t pmap,
592 int flags,
593 vm_paddr_t *lastpaddrp,
594 int *segp,
595 int first)
d7f50089 596{
20d01610
SZ
597 vm_offset_t vaddr;
598 vm_paddr_t paddr, nextpaddr;
599 bus_dma_segment_t *sg;
600 bus_addr_t bmask;
601 int seg, error = 0;
d7f50089
YY
602
603 if (map == NULL)
604 map = &nobounce_dmamap;
605
20d01610
SZ
606#ifdef INVARIANTS
607 if (dmat->flags & BUS_DMA_ALIGNED)
608 KKASSERT(((uintptr_t)buf & (dmat->alignment - 1)) == 0);
609#endif
610
d7f50089
YY
611 /*
612 * If we are being called during a callback, pagesneeded will
613 * be non-zero, so we can avoid doing the work twice.
614 */
20d01610
SZ
615 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) &&
616 map != &nobounce_dmamap && map->pagesneeded == 0) {
617 vm_offset_t vendaddr;
d7f50089
YY
618
619 /*
620 * Count the number of bounce pages
621 * needed in order to complete this transfer
622 */
20d01610 623 vaddr = (vm_offset_t)buf;
d7f50089
YY
624 vendaddr = (vm_offset_t)buf + buflen;
625
626 while (vaddr < vendaddr) {
20d01610
SZ
627 paddr = _bus_dma_extract(pmap, vaddr);
628 if (run_filter(dmat, paddr) != 0)
d7f50089 629 map->pagesneeded++;
20d01610 630 vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK));
d7f50089
YY
631 }
632 }
633
634 /* Reserve Necessary Bounce Pages */
635 if (map->pagesneeded != 0) {
20d01610 636 struct bounce_zone *bz;
d7f50089 637
20d01610
SZ
638 bz = dmat->bounce_zone;
639 BZ_LOCK(bz);
640 if (flags & BUS_DMA_NOWAIT) {
641 if (reserve_bounce_pages(dmat, map, 0) != 0) {
642 BZ_UNLOCK(bz);
643 error = ENOMEM;
644 goto free_bounce;
645 }
646 } else {
647 if (reserve_bounce_pages(dmat, map, 1) != 0) {
648 /* Queue us for resources */
649 map->dmat = dmat;
650 map->buf = buf;
651 map->buflen = buflen;
652
653 STAILQ_INSERT_TAIL(
654 &dmat->bounce_zone->bounce_map_waitinglist,
655 map, links);
656 BZ_UNLOCK(bz);
657
658 return (EINPROGRESS);
659 }
d7f50089 660 }
20d01610 661 BZ_UNLOCK(bz);
d7f50089
YY
662 }
663
20d01610
SZ
664 KKASSERT(*segp >= 1 && *segp <= nsegments);
665 seg = *segp;
666 sg = &segments[seg - 1];
667
d7f50089 668 vaddr = (vm_offset_t)buf;
20d01610
SZ
669 nextpaddr = *lastpaddrp;
670 bmask = ~(dmat->boundary - 1); /* note: will be 0 if boundary is 0 */
d7f50089 671
20d01610 672 /* force at least one segment */
d7f50089 673 do {
20d01610 674 bus_size_t size;
d7f50089 675
20d01610
SZ
676 /*
677 * Per-page main loop
678 */
679 paddr = _bus_dma_extract(pmap, vaddr);
d7f50089
YY
680 size = PAGE_SIZE - (paddr & PAGE_MASK);
681 if (size > buflen)
682 size = buflen;
d7f50089 683 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
20d01610
SZ
684 /*
685 * note: this paddr has the same in-page offset
686 * as vaddr and thus the paddr above, so the
687 * size does not have to be recalculated
688 */
d7f50089
YY
689 paddr = add_bounce_page(dmat, map, vaddr, size);
690 }
691
20d01610
SZ
692 /*
693 * Fill in the bus_dma_segment
694 */
695 if (first) {
d7f50089
YY
696 sg->ds_addr = paddr;
697 sg->ds_len = size;
20d01610 698 first = 0;
d7f50089
YY
699 } else if (paddr == nextpaddr) {
700 sg->ds_len += size;
701 } else {
d7f50089
YY
702 sg++;
703 seg++;
20d01610 704 if (seg > nsegments)
d7f50089
YY
705 break;
706 sg->ds_addr = paddr;
707 sg->ds_len = size;
708 }
d7f50089 709 nextpaddr = paddr + size;
20d01610
SZ
710
711 /*
712 * Handle maxsegsz and boundary issues with a nested loop
713 */
714 for (;;) {
715 bus_size_t tmpsize;
716
717 /*
718 * Limit to the boundary and maximum segment size
719 */
720 if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) {
721 tmpsize = dmat->boundary -
722 (sg->ds_addr & ~bmask);
723 if (tmpsize > dmat->maxsegsz)
724 tmpsize = dmat->maxsegsz;
725 KKASSERT(tmpsize < sg->ds_len);
726 } else if (sg->ds_len > dmat->maxsegsz) {
727 tmpsize = dmat->maxsegsz;
728 } else {
729 break;
730 }
731
732 /*
733 * Futz, split the data into a new segment.
734 */
735 if (seg >= nsegments)
736 goto fail;
737 sg[1].ds_len = sg[0].ds_len - tmpsize;
738 sg[1].ds_addr = sg[0].ds_addr + tmpsize;
739 sg[0].ds_len = tmpsize;
740 sg++;
741 seg++;
742 }
743
744 /*
745 * Adjust for loop
746 */
d7f50089 747 buflen -= size;
20d01610 748 vaddr += size;
d7f50089 749 } while (buflen > 0);
20d01610
SZ
750fail:
751 if (buflen != 0)
d7f50089 752 error = EFBIG;
d7f50089 753
20d01610
SZ
754 *segp = seg;
755 *lastpaddrp = nextpaddr;
d7f50089 756
20d01610
SZ
757free_bounce:
758 if (error && (dmat->flags & BUS_DMA_COULD_BOUNCE) &&
759 map != &nobounce_dmamap) {
760 _bus_dmamap_unload(dmat, map);
761 return_bounce_pages(dmat, map);
762 }
763 return error;
d7f50089
YY
764}
765
766/*
20d01610 767 * Map the buffer buf into bus space using the dmamap map.
d7f50089 768 */
20d01610
SZ
769int
770bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
771 bus_size_t buflen, bus_dmamap_callback_t *callback,
772 void *callback_arg, int flags)
d7f50089 773{
6eed46e7
MD
774 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
775 bus_dma_segment_t *segments;
20d01610
SZ
776 vm_paddr_t lastaddr = 0;
777 int error, nsegs = 1;
d7f50089 778
20d01610 779 if (map != NULL) {
d7f50089 780 /*
20d01610
SZ
781 * XXX
782 * Follow old semantics. Once all of the callers are fixed,
783 * we should get rid of these internal flag "adjustment".
d7f50089 784 */
20d01610
SZ
785 flags &= ~BUS_DMA_NOWAIT;
786 flags |= BUS_DMA_WAITOK;
d7f50089 787
20d01610
SZ
788 map->callback = callback;
789 map->callback_arg = callback_arg;
d7f50089
YY
790 }
791
6eed46e7 792 segments = bus_dma_tag_lock(dmat, cache_segments);
20d01610 793 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen,
6eed46e7 794 segments, dmat->nsegments,
20d01610 795 NULL, flags, &lastaddr, &nsegs, 1);
6eed46e7
MD
796 if (error == EINPROGRESS) {
797 bus_dma_tag_unlock(dmat);
20d01610 798 return error;
6eed46e7 799 }
d7f50089 800
6eed46e7
MD
801 callback(callback_arg, segments, nsegs, error);
802 callback(callback_arg, segments, nsegs, error);
803 bus_dma_tag_unlock(dmat);
20d01610 804 return 0;
d7f50089
YY
805}
806
807/*
808 * Like _bus_dmamap_load(), but for mbufs.
809 */
810int
811bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
812 struct mbuf *m0,
813 bus_dmamap_callback2_t *callback, void *callback_arg,
814 int flags)
815{
6eed46e7
MD
816 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
817 bus_dma_segment_t *segments;
d7f50089
YY
818 int nsegs, error;
819
20d01610
SZ
820 /*
821 * XXX
822 * Follow old semantics. Once all of the callers are fixed,
823 * we should get rid of these internal flag "adjustment".
824 */
825 flags &= ~BUS_DMA_WAITOK;
826 flags |= BUS_DMA_NOWAIT;
827
6eed46e7 828 segments = bus_dma_tag_lock(dmat, cache_segments);
20d01610 829 error = bus_dmamap_load_mbuf_segment(dmat, map, m0,
6eed46e7 830 segments, dmat->nsegments, &nsegs, flags);
20d01610
SZ
831 if (error) {
832 /* force "no valid mappings" in callback */
6eed46e7
MD
833 callback(callback_arg, segments, 0,
834 0, error);
20d01610 835 } else {
6eed46e7 836 callback(callback_arg, segments, nsegs,
20d01610
SZ
837 m0->m_pkthdr.len, error);
838 }
6eed46e7 839 bus_dma_tag_unlock(dmat);
20d01610
SZ
840 return error;
841}
842
843int
844bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat, bus_dmamap_t map,
845 struct mbuf *m0,
846 bus_dma_segment_t *segs, int maxsegs,
847 int *nsegs, int flags)
848{
849 int error;
850
851 M_ASSERTPKTHDR(m0);
852
853 KASSERT(maxsegs >= 1, ("invalid maxsegs %d\n", maxsegs));
854 KASSERT(maxsegs <= dmat->nsegments,
855 ("%d too many segments, dmat only support %d segments\n",
856 maxsegs, dmat->nsegments));
857 KASSERT(flags & BUS_DMA_NOWAIT,
858 ("only BUS_DMA_NOWAIT is supported\n"));
d7f50089 859
d7f50089
YY
860 if (m0->m_pkthdr.len <= dmat->maxsize) {
861 int first = 1;
20d01610 862 vm_paddr_t lastaddr = 0;
d7f50089
YY
863 struct mbuf *m;
864
20d01610
SZ
865 *nsegs = 1;
866 error = 0;
d7f50089 867 for (m = m0; m != NULL && error == 0; m = m->m_next) {
20d01610 868 if (m->m_len == 0)
d7f50089 869 continue;
20d01610
SZ
870
871 error = _bus_dmamap_load_buffer(dmat, map,
d7f50089 872 m->m_data, m->m_len,
20d01610
SZ
873 segs, maxsegs,
874 NULL, flags, &lastaddr,
875 nsegs, first);
876 if (error == ENOMEM && !first) {
877 /*
878 * Out of bounce pages due to too many
879 * fragments in the mbuf chain; return
880 * EFBIG instead.
881 */
882 error = EFBIG;
883 }
d7f50089
YY
884 first = 0;
885 }
20d01610
SZ
886#ifdef INVARIANTS
887 if (!error)
888 KKASSERT(*nsegs <= maxsegs && *nsegs >= 1);
889#endif
d7f50089 890 } else {
20d01610 891 *nsegs = 0;
d7f50089
YY
892 error = EINVAL;
893 }
20d01610
SZ
894 KKASSERT(error != EINPROGRESS);
895 return error;
d7f50089
YY
896}
897
898/*
899 * Like _bus_dmamap_load(), but for uios.
900 */
901int
902bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
903 struct uio *uio,
904 bus_dmamap_callback2_t *callback, void *callback_arg,
905 int flags)
906{
20d01610 907 vm_paddr_t lastaddr;
d7f50089
YY
908 int nsegs, error, first, i;
909 bus_size_t resid;
910 struct iovec *iov;
20d01610 911 pmap_t pmap;
6eed46e7
MD
912 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
913 bus_dma_segment_t *segments;
914 bus_dma_segment_t *segs;
915 int nsegs_left;
916
917 if (dmat->nsegments <= BUS_DMA_CACHE_SEGMENTS)
918 segments = cache_segments;
919 else
920 segments = kmalloc(sizeof(bus_dma_segment_t) * dmat->nsegments,
921 M_DEVBUF, M_WAITOK | M_ZERO);
d7f50089 922
20d01610
SZ
923 /*
924 * XXX
925 * Follow old semantics. Once all of the callers are fixed,
926 * we should get rid of these internal flag "adjustment".
927 */
928 flags &= ~BUS_DMA_WAITOK;
929 flags |= BUS_DMA_NOWAIT;
d7f50089
YY
930
931 resid = uio->uio_resid;
932 iov = uio->uio_iov;
933
6eed46e7
MD
934 segs = segments;
935 nsegs_left = dmat->nsegments;
936
d7f50089 937 if (uio->uio_segflg == UIO_USERSPACE) {
20d01610
SZ
938 struct thread *td;
939
d7f50089
YY
940 td = uio->uio_td;
941 KASSERT(td != NULL && td->td_proc != NULL,
942 ("bus_dmamap_load_uio: USERSPACE but no proc"));
20d01610
SZ
943 pmap = vmspace_pmap(td->td_proc->p_vmspace);
944 } else {
945 pmap = NULL;
d7f50089
YY
946 }
947
d7f50089 948 error = 0;
20d01610 949 nsegs = 1;
d7f50089 950 first = 1;
20d01610 951 lastaddr = 0;
d7f50089
YY
952 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
953 /*
954 * Now at the first iovec to load. Load each iovec
955 * until we have exhausted the residual count.
956 */
957 bus_size_t minlen =
958 resid < iov[i].iov_len ? resid : iov[i].iov_len;
959 caddr_t addr = (caddr_t) iov[i].iov_base;
960
20d01610 961 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen,
6eed46e7 962 segs, nsegs_left,
20d01610 963 pmap, flags, &lastaddr, &nsegs, first);
d7f50089
YY
964 first = 0;
965
966 resid -= minlen;
6eed46e7
MD
967 if (error == 0) {
968 nsegs_left -= nsegs;
969 segs += nsegs;
970 }
d7f50089
YY
971 }
972
6eed46e7
MD
973 /*
974 * Minimum one DMA segment, even if 0-length buffer.
975 */
976 if (nsegs_left == dmat->nsegments)
977 --nsegs_left;
978
d7f50089
YY
979 if (error) {
980 /* force "no valid mappings" in callback */
6eed46e7
MD
981 callback(callback_arg, segments, 0,
982 0, error);
d7f50089 983 } else {
6eed46e7 984 callback(callback_arg, segments, dmat->nsegments - nsegs_left,
20d01610 985 uio->uio_resid, error);
d7f50089 986 }
6eed46e7
MD
987 if (dmat->nsegments > BUS_DMA_CACHE_SEGMENTS)
988 kfree(segments, M_DEVBUF);
20d01610 989 return error;
d7f50089
YY
990}
991
992/*
993 * Release the mapping held by map.
994 */
995void
996_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
997{
998 struct bounce_page *bpage;
999
1000 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
1001 STAILQ_REMOVE_HEAD(&map->bpages, links);
1002 free_bounce_page(dmat, bpage);
1003 }
1004}
1005
1006void
1007_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
1008{
1009 struct bounce_page *bpage;
1010
1011 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
d7f50089
YY
1012 /*
1013 * Handle data bouncing. We might also
1014 * want to add support for invalidating
1015 * the caches on broken hardware
1016 */
1017 switch (op) {
1018 case BUS_DMASYNC_PREWRITE:
1019 while (bpage != NULL) {
1020 bcopy((void *)bpage->datavaddr,
1021 (void *)bpage->vaddr,
1022 bpage->datacount);
1023 bpage = STAILQ_NEXT(bpage, links);
1024 }
20d01610 1025 dmat->bounce_zone->total_bounced++;
d7f50089
YY
1026 break;
1027
1028 case BUS_DMASYNC_POSTREAD:
1029 while (bpage != NULL) {
1030 bcopy((void *)bpage->vaddr,
1031 (void *)bpage->datavaddr,
1032 bpage->datacount);
1033 bpage = STAILQ_NEXT(bpage, links);
1034 }
20d01610 1035 dmat->bounce_zone->total_bounced++;
d7f50089 1036 break;
20d01610 1037
d7f50089
YY
1038 case BUS_DMASYNC_PREREAD:
1039 case BUS_DMASYNC_POSTWRITE:
1040 /* No-ops */
1041 break;
1042 }
1043 }
1044}
1045
1046static int
20d01610 1047alloc_bounce_zone(bus_dma_tag_t dmat)
d7f50089 1048{
20d01610
SZ
1049 struct bounce_zone *bz, *new_bz;
1050 lwkt_tokref ref;
1051
1052 KASSERT(dmat->bounce_zone == NULL,
1053 ("bounce zone was already assigned\n"));
1054
1055 new_bz = kmalloc(sizeof(*new_bz), M_DEVBUF, M_INTWAIT | M_ZERO);
d7f50089 1056
20d01610
SZ
1057 lwkt_gettoken(&ref, &bounce_zone_tok);
1058
1059 /* Check to see if we already have a suitable zone */
1060 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1061 if (dmat->alignment <= bz->alignment &&
1062 dmat->lowaddr >= bz->lowaddr) {
1063 lwkt_reltoken(&ref);
1064
1065 dmat->bounce_zone = bz;
1066 kfree(new_bz, M_DEVBUF);
1067 return 0;
1068 }
d7f50089 1069 }
20d01610
SZ
1070 bz = new_bz;
1071
1072#ifdef SMP
1073 spin_init(&bz->spin);
1074#endif
1075 STAILQ_INIT(&bz->bounce_page_list);
1076 STAILQ_INIT(&bz->bounce_map_waitinglist);
1077 bz->free_bpages = 0;
1078 bz->reserved_bpages = 0;
1079 bz->active_bpages = 0;
1080 bz->lowaddr = dmat->lowaddr;
1081 bz->alignment = round_page(dmat->alignment);
1082 ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1083 busdma_zonecount++;
1084 ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1085 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1086
1087 lwkt_reltoken(&ref);
1088
1089 dmat->bounce_zone = bz;
1090
1091 sysctl_ctx_init(&bz->sysctl_ctx);
1092 bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx,
1093 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1094 CTLFLAG_RD, 0, "");
1095 if (bz->sysctl_tree == NULL) {
1096 sysctl_ctx_free(&bz->sysctl_ctx);
1097 return 0; /* XXX error code? */
1098 }
1099
1100 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1101 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1102 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1103 "Total bounce pages");
1104 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1105 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1106 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1107 "Free bounce pages");
1108 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1109 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1110 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1111 "Reserved bounce pages");
1112 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1113 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1114 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1115 "Active bounce pages");
1116 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1117 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1118 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1119 "Total bounce requests");
1120 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1121 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1122 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1123 "Total bounce requests that were deferred");
1124 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1125 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1126 "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0,
1127 "Total bounce page reservations that were failed");
1128 SYSCTL_ADD_STRING(&bz->sysctl_ctx,
1129 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1130 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1131 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1132 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1133 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1134
1135 return 0;
1136}
1137
1138static int
1139alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages, int flags)
1140{
1141 struct bounce_zone *bz = dmat->bounce_zone;
1142 int count = 0, mflags;
1143
1144 if (flags & BUS_DMA_NOWAIT)
1145 mflags = M_NOWAIT;
1146 else
1147 mflags = M_WAITOK;
1148
d7f50089
YY
1149 while (numpages > 0) {
1150 struct bounce_page *bpage;
1151
20d01610 1152 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO);
d7f50089 1153
d7f50089 1154 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
20d01610
SZ
1155 mflags, 0ul,
1156 bz->lowaddr,
1157 bz->alignment, 0);
1158 if (bpage->vaddr == 0) {
d7f50089
YY
1159 kfree(bpage, M_DEVBUF);
1160 break;
1161 }
1162 bpage->busaddr = pmap_kextract(bpage->vaddr);
20d01610
SZ
1163
1164 BZ_LOCK(bz);
1165 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1166 total_bounce_pages++;
1167 bz->total_bpages++;
1168 bz->free_bpages++;
1169 BZ_UNLOCK(bz);
1170
d7f50089
YY
1171 count++;
1172 numpages--;
1173 }
20d01610 1174 return count;
d7f50089
YY
1175}
1176
20d01610 1177/* Assume caller holds bounce zone spinlock */
d7f50089 1178static int
20d01610 1179reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
d7f50089 1180{
20d01610 1181 struct bounce_zone *bz = dmat->bounce_zone;
d7f50089
YY
1182 int pages;
1183
20d01610
SZ
1184 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1185 if (!commit && map->pagesneeded > (map->pagesreserved + pages)) {
1186 bz->reserve_failed++;
1187 return (map->pagesneeded - (map->pagesreserved + pages));
1188 }
1189
1190 bz->free_bpages -= pages;
1191
1192 bz->reserved_bpages += pages;
1193 KKASSERT(bz->reserved_bpages <= bz->total_bpages);
1194
d7f50089
YY
1195 map->pagesreserved += pages;
1196 pages = map->pagesneeded - map->pagesreserved;
1197
20d01610
SZ
1198 return pages;
1199}
1200
1201static void
1202return_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
1203{
1204 struct bounce_zone *bz = dmat->bounce_zone;
1205 int reserved = map->pagesreserved;
1206 bus_dmamap_t wait_map;
1207
1208 map->pagesreserved = 0;
1209 map->pagesneeded = 0;
1210
1211 if (reserved == 0)
1212 return;
1213
1214 BZ_LOCK(bz);
1215
1216 bz->free_bpages += reserved;
1217 KKASSERT(bz->free_bpages <= bz->total_bpages);
1218
1219 KKASSERT(bz->reserved_bpages >= reserved);
1220 bz->reserved_bpages -= reserved;
1221
1222 wait_map = get_map_waiting(dmat);
1223
1224 BZ_UNLOCK(bz);
1225
1226 if (wait_map != NULL)
1227 add_map_callback(map);
d7f50089
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1228}
1229
1230static bus_addr_t
1231add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1232 bus_size_t size)
1233{
20d01610 1234 struct bounce_zone *bz = dmat->bounce_zone;
d7f50089
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1235 struct bounce_page *bpage;
1236
20d01610 1237 KASSERT(map->pagesneeded > 0, ("map doesn't need any pages"));
d7f50089
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1238 map->pagesneeded--;
1239
20d01610 1240 KASSERT(map->pagesreserved > 0, ("map doesn't reserve any pages"));
d7f50089
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1241 map->pagesreserved--;
1242
20d01610 1243 BZ_LOCK(bz);
d7f50089 1244
20d01610
SZ
1245 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1246 KASSERT(bpage != NULL, ("free page list is empty"));
1247 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1248
1249 KKASSERT(bz->reserved_bpages > 0);
1250 bz->reserved_bpages--;
1251
1252 bz->active_bpages++;
1253 KKASSERT(bz->active_bpages <= bz->total_bpages);
1254
1255 BZ_UNLOCK(bz);
d7f50089
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1256
1257 bpage->datavaddr = vaddr;
1258 bpage->datacount = size;
20d01610
SZ
1259 STAILQ_INSERT_TAIL(&map->bpages, bpage, links);
1260 return bpage->busaddr;
d7f50089
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1261}
1262
1263static void
1264free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1265{
20d01610
SZ
1266 struct bounce_zone *bz = dmat->bounce_zone;
1267 bus_dmamap_t map;
d7f50089
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1268
1269 bpage->datavaddr = 0;
1270 bpage->datacount = 0;
1271
20d01610
SZ
1272 BZ_LOCK(bz);
1273
1274 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1275
1276 bz->free_bpages++;
1277 KKASSERT(bz->free_bpages <= bz->total_bpages);
1278
1279 KKASSERT(bz->active_bpages > 0);
1280 bz->active_bpages--;
1281
1282 map = get_map_waiting(dmat);
1283
1284 BZ_UNLOCK(bz);
1285
1286 if (map != NULL)
1287 add_map_callback(map);
1288}
1289
1290/* Assume caller holds bounce zone spinlock */
1291static bus_dmamap_t
1292get_map_waiting(bus_dma_tag_t dmat)
1293{
1294 struct bounce_zone *bz = dmat->bounce_zone;
1295 bus_dmamap_t map;
1296
1297 map = STAILQ_FIRST(&bz->bounce_map_waitinglist);
1298 if (map != NULL) {
1299 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1300 STAILQ_REMOVE_HEAD(&bz->bounce_map_waitinglist, links);
1301 bz->total_deferred++;
1302 } else {
1303 map = NULL;
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1304 }
1305 }
20d01610 1306 return map;
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1307}
1308
20d01610
SZ
1309static void
1310add_map_callback(bus_dmamap_t map)
1311{
1312 /* XXX callbacklist is not MPSAFE */
1313 crit_enter();
1314 get_mplock();
1315 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, map, links);
1316 busdma_swi_pending = 1;
1317 setsoftvm();
1318 rel_mplock();
1319 crit_exit();
1320}
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1321
1322void
1323busdma_swi(void)
1324{
20d01610 1325 bus_dmamap_t map;
d7f50089
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1326
1327 crit_enter();
1328 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1329 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1330 crit_exit();
1331 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1332 map->callback, map->callback_arg, /*flags*/0);
1333 crit_enter();
1334 }
1335 crit_exit();
1336}