2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
34 #include <sys/interrupt.h>
35 #include <sys/kernel.h>
39 #include <sys/mutex.h>
42 #include <sys/sysctl.h>
45 #include <vm/vm_page.h>
46 #include <vm/vm_map.h>
48 #include <machine/atomic.h>
49 #include <machine/bus.h>
50 #include <machine/md_var.h>
51 #include <machine/specialreg.h>
54 #define MAX_BPAGES 512
56 #define MAX_BPAGES 8192
58 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
59 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
69 bus_dma_filter_t *filter;
77 bus_dma_lock_t *lockfunc;
79 bus_dma_segment_t *segments;
80 struct bounce_zone *bounce_zone;
84 vm_offset_t vaddr; /* kva of bounce buffer */
85 bus_addr_t busaddr; /* Physical address */
86 vm_offset_t datavaddr; /* kva of client data */
87 bus_size_t datacount; /* client data count */
88 STAILQ_ENTRY(bounce_page) links;
91 int busdma_swi_pending;
94 STAILQ_ENTRY(bounce_zone) links;
95 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
103 bus_size_t alignment;
107 struct sysctl_ctx_list sysctl_tree;
108 struct sysctl_oid *sysctl_tree_top;
111 static struct mtx bounce_lock;
112 static int total_bpages;
113 static int busdma_zonecount;
114 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
116 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
117 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
118 "Total bounce pages");
121 struct bp_list bpages;
125 void *buf; /* unmapped buffer pointer */
126 bus_size_t buflen; /* unmapped buffer length */
127 bus_dmamap_callback_t *callback;
129 STAILQ_ENTRY(bus_dmamap) links;
132 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
133 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
134 static struct bus_dmamap nobounce_dmamap;
136 static void init_bounce_pages(void *dummy);
137 static int alloc_bounce_zone(bus_dma_tag_t dmat);
138 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
139 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
141 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
142 vm_offset_t vaddr, bus_size_t size);
143 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
144 int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
145 int _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
146 void *buf, bus_size_t buflen, int flags);
150 #define pmap_kextract pmap_kextract_ma
154 * Return true if a match is made.
156 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
158 * If paddr is within the bounds of the dma tag then call the filter callback
159 * to check for a match, if there is no filter callback then assume a match.
162 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
169 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr)
170 || ((paddr & (dmat->alignment - 1)) != 0))
171 && (dmat->filter == NULL
172 || (*dmat->filter)(dmat->filterarg, paddr) != 0))
176 } while (retval == 0 && dmat != NULL);
181 * Convenience function for manipulating driver locks from busdma (during
182 * busdma_swi, for example). Drivers that don't provide their own locks
183 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
184 * non-mutex locking scheme don't have to use this at all.
187 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
191 dmtx = (struct mtx *)arg;
200 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
205 * dflt_lock should never get called. It gets put into the dma tag when
206 * lockfunc == NULL, which is only valid if the maps that are associated
207 * with the tag are meant to never be defered.
208 * XXX Should have a way to identify which driver is responsible here.
211 dflt_lock(void *arg, bus_dma_lock_op_t op)
213 panic("driver error: busdma dflt_lock called");
217 * Allocate a device specific dma_tag.
220 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
221 bus_size_t boundary, bus_addr_t lowaddr,
222 bus_addr_t highaddr, bus_dma_filter_t *filter,
223 void *filterarg, bus_size_t maxsize, int nsegments,
224 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
225 void *lockfuncarg, bus_dma_tag_t *dmat)
227 bus_dma_tag_t newtag;
230 /* Always enforce at least a 4GB (2GB for PAE) boundary. */
231 #if defined(__amd64__)
232 if (boundary == 0 || boundary > ((bus_addr_t)1 << 32))
233 boundary = (bus_size_t)1 << 32;
235 if (boundary == 0 || boundary > ((bus_addr_t)1 << 31))
236 boundary = (bus_size_t)1 << 31;
238 /* Basic sanity checking */
239 if (boundary != 0 && boundary < maxsegsz)
246 /* Return a NULL tag on failure */
249 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
251 if (newtag == NULL) {
252 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
253 __func__, newtag, 0, error);
257 newtag->parent = parent;
258 newtag->alignment = alignment;
259 newtag->boundary = boundary;
260 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
261 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
262 newtag->filter = filter;
263 newtag->filterarg = filterarg;
264 newtag->maxsize = maxsize;
265 newtag->nsegments = nsegments;
266 newtag->maxsegsz = maxsegsz;
267 newtag->flags = flags;
268 newtag->ref_count = 1; /* Count ourself */
269 newtag->map_count = 0;
270 if (lockfunc != NULL) {
271 newtag->lockfunc = lockfunc;
272 newtag->lockfuncarg = lockfuncarg;
274 newtag->lockfunc = dflt_lock;
275 newtag->lockfuncarg = NULL;
277 newtag->segments = NULL;
279 /* Take into account any restrictions imposed by our parent tag */
280 if (parent != NULL) {
281 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
282 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
283 if (newtag->boundary == 0)
284 newtag->boundary = parent->boundary;
285 else if (parent->boundary != 0)
286 newtag->boundary = MIN(parent->boundary,
288 if ((newtag->filter != NULL) ||
289 ((parent->flags & BUS_DMA_COULD_BOUNCE) != 0))
290 newtag->flags |= BUS_DMA_COULD_BOUNCE;
291 if (newtag->filter == NULL) {
293 * Short circuit looking at our parent directly
294 * since we have encapsulated all of its information
296 newtag->filter = parent->filter;
297 newtag->filterarg = parent->filterarg;
298 newtag->parent = parent->parent;
300 if (newtag->parent != NULL)
301 atomic_add_int(&parent->ref_count, 1);
304 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem)
305 || newtag->alignment > 1)
306 newtag->flags |= BUS_DMA_COULD_BOUNCE;
308 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
309 (flags & BUS_DMA_ALLOCNOW) != 0) {
310 struct bounce_zone *bz;
314 if ((error = alloc_bounce_zone(newtag)) != 0) {
315 free(newtag, M_DEVBUF);
318 bz = newtag->bounce_zone;
320 if (ptoa(bz->total_bpages) < maxsize) {
323 pages = atop(maxsize) - bz->total_bpages;
325 /* Add pages to our bounce pool */
326 if (alloc_bounce_pages(newtag, pages) < pages)
329 /* Performed initial allocation */
330 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
334 free(newtag, M_DEVBUF);
338 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
339 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
344 bus_dma_tag_destroy(bus_dma_tag_t dmat)
346 bus_dma_tag_t dmat_copy;
354 if (dmat->map_count != 0) {
359 while (dmat != NULL) {
360 bus_dma_tag_t parent;
362 parent = dmat->parent;
363 atomic_subtract_int(&dmat->ref_count, 1);
364 if (dmat->ref_count == 0) {
365 if (dmat->segments != NULL)
366 free(dmat->segments, M_DEVBUF);
367 free(dmat, M_DEVBUF);
369 * Last reference count, so
370 * release our reference
371 * count on our parent.
379 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
384 * Allocate a handle for mapping from kva/uva/physical
385 * address space into bus device space.
388 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
394 if (dmat->segments == NULL) {
395 dmat->segments = (bus_dma_segment_t *)malloc(
396 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
398 if (dmat->segments == NULL) {
399 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
400 __func__, dmat, ENOMEM);
406 * Bouncing might be required if the driver asks for an active
407 * exclusion region, a data alignment that is stricter than 1, and/or
408 * an active address boundary.
410 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
413 struct bounce_zone *bz;
416 if (dmat->bounce_zone == NULL) {
417 if ((error = alloc_bounce_zone(dmat)) != 0)
420 bz = dmat->bounce_zone;
422 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
425 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
426 __func__, dmat, ENOMEM);
430 /* Initialize the new map */
431 STAILQ_INIT(&((*mapp)->bpages));
434 * Attempt to add pages to our pool on a per-instance
435 * basis up to a sane limit.
437 if (dmat->alignment > 1)
438 maxpages = MAX_BPAGES;
440 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
441 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
442 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
445 pages = MAX(atop(dmat->maxsize), 1);
446 pages = MIN(maxpages - bz->total_bpages, pages);
447 pages = MAX(pages, 1);
448 if (alloc_bounce_pages(dmat, pages) < pages)
451 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
453 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
464 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
465 __func__, dmat, dmat->flags, error);
470 * Destroy a handle for mapping from kva/uva/physical
471 * address space into bus device space.
474 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
476 if (map != NULL && map != &nobounce_dmamap) {
477 if (STAILQ_FIRST(&map->bpages) != NULL) {
478 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
479 __func__, dmat, EBUSY);
482 if (dmat->bounce_zone)
483 dmat->bounce_zone->map_count--;
487 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
493 * Allocate a piece of memory that can be efficiently mapped into
494 * bus device space based on the constraints lited in the dma tag.
495 * A dmamap to for use with dmamap_load is also allocated.
498 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
503 if (flags & BUS_DMA_NOWAIT)
508 /* If we succeed, no mapping/bouncing will be required */
511 if (dmat->segments == NULL) {
512 dmat->segments = (bus_dma_segment_t *)malloc(
513 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
515 if (dmat->segments == NULL) {
516 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
517 __func__, dmat, dmat->flags, ENOMEM);
521 if (flags & BUS_DMA_ZERO)
526 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
527 * alignment guarantees of malloc need to be nailed down, and the
528 * code below should be rewritten to take that into account.
530 * In the meantime, we'll warn the user if malloc gets it wrong.
532 if ((dmat->maxsize <= PAGE_SIZE) &&
533 (dmat->alignment < dmat->maxsize) &&
534 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem)) {
535 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
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 * XXX Certain AGP hardware does.
543 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
544 0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
547 if (*vaddr == NULL) {
548 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
549 __func__, dmat, dmat->flags, ENOMEM);
551 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
552 printf("bus_dmamem_alloc failed to align memory properly.\n");
554 if (flags & BUS_DMA_NOCACHE)
555 pmap_change_attr((vm_offset_t)*vaddr, dmat->maxsize,
557 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
558 __func__, dmat, dmat->flags, 0);
563 * Free a piece of memory and it's allociated dmamap, that was allocated
564 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
567 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
570 * dmamem does not need to be bounced, so the map should be
574 panic("bus_dmamem_free: Invalid map freed\n");
575 pmap_change_attr((vm_offset_t)vaddr, dmat->maxsize, PAT_WRITE_BACK);
576 if ((dmat->maxsize <= PAGE_SIZE) &&
577 (dmat->alignment < dmat->maxsize) &&
578 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem))
579 free(vaddr, M_DEVBUF);
581 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
583 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
587 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
588 void *buf, bus_size_t buflen, int flags)
591 vm_offset_t vendaddr;
594 if ((map != &nobounce_dmamap && map->pagesneeded == 0)) {
595 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
596 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
597 dmat->boundary, dmat->alignment);
598 CTR3(KTR_BUSDMA, "map= %p, nobouncemap= %p, pagesneeded= %d",
599 map, &nobounce_dmamap, map->pagesneeded);
601 * Count the number of bounce pages
602 * needed in order to complete this transfer
604 vaddr = (vm_offset_t)buf;
605 vendaddr = (vm_offset_t)buf + buflen;
607 while (vaddr < vendaddr) {
610 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
612 paddr = pmap_extract(pmap, vaddr);
614 paddr = pmap_kextract(vaddr);
615 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
616 run_filter(dmat, paddr) != 0) {
617 sg_len = roundup2(sg_len, dmat->alignment);
622 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
625 /* Reserve Necessary Bounce Pages */
626 if (map->pagesneeded != 0) {
627 mtx_lock(&bounce_lock);
628 if (flags & BUS_DMA_NOWAIT) {
629 if (reserve_bounce_pages(dmat, map, 0) != 0) {
630 mtx_unlock(&bounce_lock);
634 if (reserve_bounce_pages(dmat, map, 1) != 0) {
635 /* Queue us for resources */
638 map->buflen = buflen;
639 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
641 mtx_unlock(&bounce_lock);
642 return (EINPROGRESS);
645 mtx_unlock(&bounce_lock);
652 * Utility function to load a linear buffer. lastaddrp holds state
653 * between invocations (for multiple-buffer loads). segp contains
654 * the starting segment on entrace, and the ending segment on exit.
655 * first indicates if this is the first invocation of this function.
658 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
660 void *buf, bus_size_t buflen,
663 bus_addr_t *lastaddrp,
664 bus_dma_segment_t *segs,
669 bus_addr_t curaddr, lastaddr, baddr, bmask;
674 map = &nobounce_dmamap;
676 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
677 error = _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
682 vaddr = (vm_offset_t)buf;
683 lastaddr = *lastaddrp;
684 bmask = ~(dmat->boundary - 1);
686 for (seg = *segp; buflen > 0 ; ) {
687 bus_size_t max_sgsize;
690 * Get the physical address for this segment.
693 curaddr = pmap_extract(pmap, vaddr);
695 curaddr = pmap_kextract(vaddr);
698 * Compute the segment size, and adjust counts.
700 max_sgsize = MIN(buflen, dmat->maxsegsz);
701 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
702 if (((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
703 map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
704 sgsize = roundup2(sgsize, dmat->alignment);
705 sgsize = MIN(sgsize, max_sgsize);
706 curaddr = add_bounce_page(dmat, map, vaddr, sgsize);
708 sgsize = MIN(sgsize, max_sgsize);
712 * Make sure we don't cross any boundaries.
714 if (dmat->boundary > 0) {
715 baddr = (curaddr + dmat->boundary) & bmask;
716 if (sgsize > (baddr - curaddr))
717 sgsize = (baddr - curaddr);
721 * Insert chunk into a segment, coalescing with
722 * previous segment if possible.
725 segs[seg].ds_addr = curaddr;
726 segs[seg].ds_len = sgsize;
729 if (curaddr == lastaddr &&
730 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
731 (dmat->boundary == 0 ||
732 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
733 segs[seg].ds_len += sgsize;
735 if (++seg >= dmat->nsegments)
737 segs[seg].ds_addr = curaddr;
738 segs[seg].ds_len = sgsize;
742 lastaddr = curaddr + sgsize;
748 *lastaddrp = lastaddr;
753 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
757 * Map the buffer buf into bus space using the dmamap map.
760 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
761 bus_size_t buflen, bus_dmamap_callback_t *callback,
762 void *callback_arg, int flags)
764 bus_addr_t lastaddr = 0;
765 int error, nsegs = 0;
768 flags |= BUS_DMA_WAITOK;
769 map->callback = callback;
770 map->callback_arg = callback_arg;
773 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, NULL, flags,
774 &lastaddr, dmat->segments, &nsegs, 1);
776 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
777 __func__, dmat, dmat->flags, error, nsegs + 1);
779 if (error == EINPROGRESS) {
784 (*callback)(callback_arg, dmat->segments, 0, error);
786 (*callback)(callback_arg, dmat->segments, nsegs + 1, 0);
789 * Return ENOMEM to the caller so that it can pass it up the stack.
790 * This error only happens when NOWAIT is set, so deferal is disabled.
800 * Like _bus_dmamap_load(), but for mbufs.
803 _bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
804 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
811 flags |= BUS_DMA_NOWAIT;
814 if (m0->m_pkthdr.len <= dmat->maxsize) {
816 bus_addr_t lastaddr = 0;
819 for (m = m0; m != NULL && error == 0; m = m->m_next) {
821 error = _bus_dmamap_load_buffer(dmat, map,
823 NULL, flags, &lastaddr,
832 /* XXX FIXME: Having to increment nsegs is really annoying */
834 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
835 __func__, dmat, dmat->flags, error, *nsegs);
840 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
842 bus_dmamap_callback2_t *callback, void *callback_arg,
847 error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, dmat->segments, &nsegs,
851 /* force "no valid mappings" in callback */
852 (*callback)(callback_arg, dmat->segments, 0, 0, error);
854 (*callback)(callback_arg, dmat->segments,
855 nsegs, m0->m_pkthdr.len, error);
857 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
858 __func__, dmat, dmat->flags, error, nsegs);
863 bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
864 struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs,
867 return (_bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags));
871 * Like _bus_dmamap_load(), but for uios.
874 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
876 bus_dmamap_callback2_t *callback, void *callback_arg,
879 bus_addr_t lastaddr = 0;
880 int nsegs, error, first, i;
885 flags |= BUS_DMA_NOWAIT;
886 resid = uio->uio_resid;
889 if (uio->uio_segflg == UIO_USERSPACE) {
890 KASSERT(uio->uio_td != NULL,
891 ("bus_dmamap_load_uio: USERSPACE but no proc"));
892 pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
899 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
901 * Now at the first iovec to load. Load each iovec
902 * until we have exhausted the residual count.
905 resid < iov[i].iov_len ? resid : iov[i].iov_len;
906 caddr_t addr = (caddr_t) iov[i].iov_base;
909 error = _bus_dmamap_load_buffer(dmat, map,
910 addr, minlen, pmap, flags, &lastaddr,
911 dmat->segments, &nsegs, first);
919 /* force "no valid mappings" in callback */
920 (*callback)(callback_arg, dmat->segments, 0, 0, error);
922 (*callback)(callback_arg, dmat->segments,
923 nsegs+1, uio->uio_resid, error);
925 CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
926 __func__, dmat, dmat->flags, error, nsegs + 1);
931 * Release the mapping held by map.
934 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
936 struct bounce_page *bpage;
938 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
939 STAILQ_REMOVE_HEAD(&map->bpages, links);
940 free_bounce_page(dmat, bpage);
945 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
947 struct bounce_page *bpage;
949 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
951 * Handle data bouncing. We might also
952 * want to add support for invalidating
953 * the caches on broken hardware
955 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
956 "performing bounce", __func__, op, dmat, dmat->flags);
958 if (op & BUS_DMASYNC_PREWRITE) {
959 while (bpage != NULL) {
960 bcopy((void *)bpage->datavaddr,
961 (void *)bpage->vaddr,
963 bpage = STAILQ_NEXT(bpage, links);
965 dmat->bounce_zone->total_bounced++;
968 if (op & BUS_DMASYNC_POSTREAD) {
969 while (bpage != NULL) {
970 bcopy((void *)bpage->vaddr,
971 (void *)bpage->datavaddr,
973 bpage = STAILQ_NEXT(bpage, links);
975 dmat->bounce_zone->total_bounced++;
981 init_bounce_pages(void *dummy __unused)
985 STAILQ_INIT(&bounce_zone_list);
986 STAILQ_INIT(&bounce_map_waitinglist);
987 STAILQ_INIT(&bounce_map_callbacklist);
988 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
990 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
992 static struct sysctl_ctx_list *
993 busdma_sysctl_tree(struct bounce_zone *bz)
995 return (&bz->sysctl_tree);
998 static struct sysctl_oid *
999 busdma_sysctl_tree_top(struct bounce_zone *bz)
1001 return (bz->sysctl_tree_top);
1004 #if defined(__amd64__) || defined(PAE)
1005 #define SYSCTL_ADD_BUS_SIZE_T SYSCTL_ADD_UQUAD
1007 #define SYSCTL_ADD_BUS_SIZE_T(ctx, parent, nbr, name, flag, ptr, desc) \
1008 SYSCTL_ADD_UINT(ctx, parent, nbr, name, flag, ptr, 0, desc)
1012 alloc_bounce_zone(bus_dma_tag_t dmat)
1014 struct bounce_zone *bz;
1016 /* Check to see if we already have a suitable zone */
1017 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1018 if ((dmat->alignment <= bz->alignment)
1019 && (dmat->lowaddr >= bz->lowaddr)) {
1020 dmat->bounce_zone = bz;
1025 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
1026 M_NOWAIT | M_ZERO)) == NULL)
1029 STAILQ_INIT(&bz->bounce_page_list);
1030 bz->free_bpages = 0;
1031 bz->reserved_bpages = 0;
1032 bz->active_bpages = 0;
1033 bz->lowaddr = dmat->lowaddr;
1034 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
1036 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1038 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1039 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1040 dmat->bounce_zone = bz;
1042 sysctl_ctx_init(&bz->sysctl_tree);
1043 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
1044 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1046 if (bz->sysctl_tree_top == NULL) {
1047 sysctl_ctx_free(&bz->sysctl_tree);
1048 return (0); /* XXX error code? */
1051 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1052 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1053 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1054 "Total bounce pages");
1055 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1056 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1057 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1058 "Free bounce pages");
1059 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1060 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1061 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1062 "Reserved bounce pages");
1063 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1064 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1065 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1066 "Active bounce pages");
1067 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1068 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1069 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1070 "Total bounce requests");
1071 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1072 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1073 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1074 "Total bounce requests that were deferred");
1075 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1076 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1077 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1078 SYSCTL_ADD_BUS_SIZE_T(busdma_sysctl_tree(bz),
1079 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1080 "alignment", CTLFLAG_RD, &bz->alignment, "");
1086 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1088 struct bounce_zone *bz;
1091 bz = dmat->bounce_zone;
1093 while (numpages > 0) {
1094 struct bounce_page *bpage;
1096 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1101 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1106 if (bpage->vaddr == 0) {
1107 free(bpage, M_DEVBUF);
1110 bpage->busaddr = pmap_kextract(bpage->vaddr);
1111 mtx_lock(&bounce_lock);
1112 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1116 mtx_unlock(&bounce_lock);
1124 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1126 struct bounce_zone *bz;
1129 mtx_assert(&bounce_lock, MA_OWNED);
1130 bz = dmat->bounce_zone;
1131 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1132 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1133 return (map->pagesneeded - (map->pagesreserved + pages));
1134 bz->free_bpages -= pages;
1135 bz->reserved_bpages += pages;
1136 map->pagesreserved += pages;
1137 pages = map->pagesneeded - map->pagesreserved;
1143 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1146 struct bounce_zone *bz;
1147 struct bounce_page *bpage;
1149 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1150 KASSERT(map != NULL && map != &nobounce_dmamap,
1151 ("add_bounce_page: bad map %p", map));
1153 bz = dmat->bounce_zone;
1154 if (map->pagesneeded == 0)
1155 panic("add_bounce_page: map doesn't need any pages");
1158 if (map->pagesreserved == 0)
1159 panic("add_bounce_page: map doesn't need any pages");
1160 map->pagesreserved--;
1162 mtx_lock(&bounce_lock);
1163 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1165 panic("add_bounce_page: free page list is empty");
1167 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1168 bz->reserved_bpages--;
1169 bz->active_bpages++;
1170 mtx_unlock(&bounce_lock);
1172 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1173 /* Page offset needs to be preserved. */
1174 bpage->vaddr |= vaddr & PAGE_MASK;
1175 bpage->busaddr |= vaddr & PAGE_MASK;
1177 bpage->datavaddr = vaddr;
1178 bpage->datacount = size;
1179 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1180 return (bpage->busaddr);
1184 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1186 struct bus_dmamap *map;
1187 struct bounce_zone *bz;
1189 bz = dmat->bounce_zone;
1190 bpage->datavaddr = 0;
1191 bpage->datacount = 0;
1192 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1194 * Reset the bounce page to start at offset 0. Other uses
1195 * of this bounce page may need to store a full page of
1196 * data and/or assume it starts on a page boundary.
1198 bpage->vaddr &= ~PAGE_MASK;
1199 bpage->busaddr &= ~PAGE_MASK;
1202 mtx_lock(&bounce_lock);
1203 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1205 bz->active_bpages--;
1206 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1207 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1208 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1209 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1211 busdma_swi_pending = 1;
1212 bz->total_deferred++;
1213 swi_sched(vm_ih, 0);
1216 mtx_unlock(&bounce_lock);
1223 struct bus_dmamap *map;
1225 mtx_lock(&bounce_lock);
1226 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1227 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1228 mtx_unlock(&bounce_lock);
1230 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1231 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1232 map->callback, map->callback_arg, /*flags*/0);
1233 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1234 mtx_lock(&bounce_lock);
1236 mtx_unlock(&bounce_lock);