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
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 $
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
35 #include <sys/bus_dma.h>
36 #include <sys/kernel.h>
37 #include <sys/sysctl.h>
40 #include <sys/thread2.h>
41 #include <sys/spinlock2.h>
42 #include <sys/mplock2.h>
45 #include <vm/vm_page.h>
47 /* XXX needed for to access pmap to convert per-proc virtual to physical */
50 #include <vm/vm_map.h>
52 #include <machine/md_var.h>
54 #define MAX_BPAGES 1024
57 * 16 x N declared on stack.
59 #define BUS_DMA_CACHE_SEGMENTS 8
70 bus_dma_filter_t *filter;
78 bus_dma_segment_t *segments;
79 struct bounce_zone *bounce_zone;
88 * bus_dma_tag private flags
90 #define BUS_DMA_BOUNCE_ALIGN BUS_DMA_BUS2
91 #define BUS_DMA_BOUNCE_LOWADDR BUS_DMA_BUS3
92 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
94 #define BUS_DMA_COULD_BOUNCE (BUS_DMA_BOUNCE_LOWADDR | BUS_DMA_BOUNCE_ALIGN)
96 #define BUS_DMAMEM_KMALLOC(dmat) \
97 ((dmat)->maxsize <= PAGE_SIZE && \
98 (dmat)->alignment <= PAGE_SIZE && \
99 (dmat)->lowaddr >= ptoa(Maxmem))
102 vm_offset_t vaddr; /* kva of bounce buffer */
103 bus_addr_t busaddr; /* Physical address */
104 vm_offset_t datavaddr; /* kva of client data */
105 bus_size_t datacount; /* client data count */
106 STAILQ_ENTRY(bounce_page) links;
110 STAILQ_ENTRY(bounce_zone) links;
111 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
112 STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
114 struct spinlock spin;
125 bus_size_t alignment;
129 struct sysctl_ctx_list sysctl_ctx;
130 struct sysctl_oid *sysctl_tree;
134 #define BZ_LOCK(bz) spin_lock(&(bz)->spin)
135 #define BZ_UNLOCK(bz) spin_unlock(&(bz)->spin)
137 #define BZ_LOCK(bz) crit_enter()
138 #define BZ_UNLOCK(bz) crit_exit()
141 static struct lwkt_token bounce_zone_tok =
142 LWKT_TOKEN_MP_INITIALIZER(bounce_zone_tok);
143 static int busdma_zonecount;
144 static STAILQ_HEAD(, bounce_zone) bounce_zone_list =
145 STAILQ_HEAD_INITIALIZER(bounce_zone_list);
147 int busdma_swi_pending;
148 static int total_bounce_pages;
149 static int max_bounce_pages = MAX_BPAGES;
150 static int bounce_alignment = 1; /* XXX temporary */
152 TUNABLE_INT("hw.busdma.max_bpages", &max_bounce_pages);
153 TUNABLE_INT("hw.busdma.bounce_alignment", &bounce_alignment);
156 struct bp_list bpages;
160 void *buf; /* unmapped buffer pointer */
161 bus_size_t buflen; /* unmapped buffer length */
162 bus_dmamap_callback_t *callback;
164 STAILQ_ENTRY(bus_dmamap) links;
167 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist =
168 STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist);
170 static struct bus_dmamap nobounce_dmamap;
172 static int alloc_bounce_zone(bus_dma_tag_t);
173 static int alloc_bounce_pages(bus_dma_tag_t, u_int, int);
174 static int reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int);
175 static void return_bounce_pages(bus_dma_tag_t, bus_dmamap_t);
176 static bus_addr_t add_bounce_page(bus_dma_tag_t, bus_dmamap_t,
177 vm_offset_t, bus_size_t);
178 static void free_bounce_page(bus_dma_tag_t, struct bounce_page *);
180 static bus_dmamap_t get_map_waiting(bus_dma_tag_t);
181 static void add_map_callback(bus_dmamap_t);
183 SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
184 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages,
185 0, "Total bounce pages");
186 SYSCTL_INT(_hw_busdma, OID_AUTO, max_bpages, CTLFLAG_RD, &max_bounce_pages,
187 0, "Max bounce pages per bounce zone");
188 SYSCTL_INT(_hw_busdma, OID_AUTO, bounce_alignment, CTLFLAG_RD,
189 &bounce_alignment, 0, "Obey alignment constraint");
192 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
198 if (((paddr > dmat->lowaddr && paddr <= dmat->highaddr) ||
199 (bounce_alignment && (paddr & (dmat->alignment - 1)) != 0))
200 && (dmat->filter == NULL ||
201 dmat->filter(dmat->filterarg, paddr) != 0))
205 } while (retval == 0 && dmat != NULL);
211 bus_dma_tag_lock(bus_dma_tag_t tag, bus_dma_segment_t *cache)
213 if (tag->nsegments <= BUS_DMA_CACHE_SEGMENTS)
216 spin_lock(&tag->spin);
218 return(tag->segments);
223 bus_dma_tag_unlock(bus_dma_tag_t tag)
226 if (tag->nsegments > BUS_DMA_CACHE_SEGMENTS)
227 spin_unlock(&tag->spin);
232 * Allocate a device specific dma_tag.
235 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
236 bus_size_t boundary, bus_addr_t lowaddr,
237 bus_addr_t highaddr, bus_dma_filter_t *filter,
238 void *filterarg, bus_size_t maxsize, int nsegments,
239 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
241 bus_dma_tag_t newtag;
250 if (alignment & (alignment - 1))
251 panic("alignment must be power of 2\n");
254 if (boundary & (boundary - 1))
255 panic("boundary must be power of 2\n");
256 if (boundary < maxsegsz) {
257 kprintf("boundary < maxsegsz:\n");
263 /* Return a NULL tag on failure */
266 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT | M_ZERO);
269 spin_init(&newtag->spin);
271 newtag->parent = parent;
272 newtag->alignment = alignment;
273 newtag->boundary = boundary;
274 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
275 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
276 newtag->filter = filter;
277 newtag->filterarg = filterarg;
278 newtag->maxsize = maxsize;
279 newtag->nsegments = nsegments;
280 newtag->maxsegsz = maxsegsz;
281 newtag->flags = flags;
282 newtag->ref_count = 1; /* Count ourself */
283 newtag->map_count = 0;
284 newtag->segments = NULL;
285 newtag->bounce_zone = NULL;
287 /* Take into account any restrictions imposed by our parent tag */
288 if (parent != NULL) {
289 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
290 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
292 if (newtag->boundary == 0) {
293 newtag->boundary = parent->boundary;
294 } else if (parent->boundary != 0) {
295 newtag->boundary = MIN(parent->boundary,
300 newtag->alignment = MAX(parent->alignment, newtag->alignment);
303 if (newtag->filter == NULL) {
305 * Short circuit looking at our parent directly
306 * since we have encapsulated all of its information
308 newtag->filter = parent->filter;
309 newtag->filterarg = parent->filterarg;
310 newtag->parent = parent->parent;
312 if (newtag->parent != NULL)
316 if (newtag->lowaddr < ptoa(Maxmem))
317 newtag->flags |= BUS_DMA_BOUNCE_LOWADDR;
318 if (bounce_alignment && newtag->alignment > 1 &&
319 !(newtag->flags & BUS_DMA_ALIGNED))
320 newtag->flags |= BUS_DMA_BOUNCE_ALIGN;
322 if ((newtag->flags & BUS_DMA_COULD_BOUNCE) &&
323 (flags & BUS_DMA_ALLOCNOW) != 0) {
324 struct bounce_zone *bz;
328 error = alloc_bounce_zone(newtag);
331 bz = newtag->bounce_zone;
333 if (ptoa(bz->total_bpages) < maxsize) {
336 if (flags & BUS_DMA_ONEBPAGE) {
339 pages = atop(round_page(maxsize)) -
341 pages = MAX(pages, 1);
344 /* Add pages to our bounce pool */
345 if (alloc_bounce_pages(newtag, pages, flags) < pages)
348 /* Performed initial allocation */
349 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
354 kfree(newtag, M_DEVBUF);
361 bus_dma_tag_destroy(bus_dma_tag_t dmat)
364 if (dmat->map_count != 0)
367 while (dmat != NULL) {
368 bus_dma_tag_t parent;
370 parent = dmat->parent;
372 if (dmat->ref_count == 0) {
373 if (dmat->segments != NULL)
374 kfree(dmat->segments, M_DEVBUF);
375 kfree(dmat, M_DEVBUF);
377 * Last reference count, so
378 * release our reference
379 * count on our parent.
390 bus_dma_tag_getmaxsize(bus_dma_tag_t tag)
392 return(tag->maxsize);
396 * Allocate a handle for mapping from kva/uva/physical
397 * address space into bus device space.
400 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
406 if (dmat->segments == NULL) {
407 KKASSERT(dmat->nsegments && dmat->nsegments < 16384);
408 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
409 dmat->nsegments, M_DEVBUF, M_INTWAIT);
412 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
413 struct bounce_zone *bz;
418 if (dmat->bounce_zone == NULL) {
419 error = alloc_bounce_zone(dmat);
423 bz = dmat->bounce_zone;
425 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO);
427 /* Initialize the new map */
428 STAILQ_INIT(&((*mapp)->bpages));
431 * Attempt to add pages to our pool on a per-instance
432 * basis up to a sane limit.
434 if (dmat->flags & BUS_DMA_BOUNCE_ALIGN) {
435 maxpages = max_bounce_pages;
437 maxpages = MIN(max_bounce_pages,
438 Maxmem - atop(dmat->lowaddr));
440 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
441 || (dmat->map_count > 0
442 && bz->total_bpages < maxpages)) {
445 if (flags & BUS_DMA_ONEBPAGE) {
448 pages = atop(round_page(dmat->maxsize));
449 pages = MIN(maxpages - bz->total_bpages, pages);
450 pages = MAX(pages, 1);
452 if (alloc_bounce_pages(dmat, pages, flags) < pages)
455 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
457 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
471 * Destroy a handle for mapping from kva/uva/physical
472 * address space into bus device space.
475 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
478 if (STAILQ_FIRST(&map->bpages) != NULL)
480 kfree(map, M_DEVBUF);
486 static __inline bus_size_t
487 check_kmalloc(bus_dma_tag_t dmat, const void *vaddr0, int verify)
489 bus_size_t maxsize = 0;
490 uintptr_t vaddr = (uintptr_t)vaddr0;
492 if ((vaddr ^ (vaddr + dmat->maxsize - 1)) & ~PAGE_MASK) {
493 if (verify || bootverbose)
494 kprintf("boundary check failed\n");
496 print_backtrace(-1); /* XXX panic */
497 maxsize = dmat->maxsize;
499 if (vaddr & (dmat->alignment - 1)) {
500 if (verify || bootverbose)
501 kprintf("alignment check failed\n");
503 print_backtrace(-1); /* XXX panic */
504 if (dmat->maxsize < dmat->alignment)
505 maxsize = dmat->alignment;
507 maxsize = dmat->maxsize;
513 * Allocate a piece of memory that can be efficiently mapped into
514 * bus device space based on the constraints lited in the dma tag.
516 * mapp is degenerate. By definition this allocation should not require
517 * bounce buffers so do not allocate a dma map.
520 bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags,
525 /* If we succeed, no mapping/bouncing will be required */
528 if (dmat->segments == NULL) {
529 KKASSERT(dmat->nsegments < 16384);
530 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
531 dmat->nsegments, M_DEVBUF, M_INTWAIT);
534 if (flags & BUS_DMA_NOWAIT)
538 if (flags & BUS_DMA_ZERO)
541 if (BUS_DMAMEM_KMALLOC(dmat)) {
544 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags);
548 * Check whether the allocation
549 * - crossed a page boundary
551 * Retry with power-of-2 alignment in the above cases.
553 maxsize = check_kmalloc(dmat, *vaddr, 0);
557 kfree(*vaddr, M_DEVBUF);
558 /* XXX check for overflow? */
559 for (size = 1; size <= maxsize; size <<= 1)
561 *vaddr = kmalloc(size, M_DEVBUF, mflags);
562 check_kmalloc(dmat, *vaddr, 1);
566 * XXX Use Contigmalloc until it is merged into this facility
567 * and handles multi-seg allocations. Nobody is doing
568 * multi-seg allocations yet though.
570 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
571 0ul, dmat->lowaddr, dmat->alignment, dmat->boundary);
579 * Free a piece of memory and it's allociated dmamap, that was allocated
580 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
583 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
586 * dmamem does not need to be bounced, so the map should be
590 panic("bus_dmamem_free: Invalid map freed\n");
591 if (BUS_DMAMEM_KMALLOC(dmat))
592 kfree(vaddr, M_DEVBUF);
594 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
597 static __inline vm_paddr_t
598 _bus_dma_extract(pmap_t pmap, vm_offset_t vaddr)
601 return pmap_extract(pmap, vaddr);
603 return pmap_kextract(vaddr);
607 * Utility function to load a linear buffer. lastaddrp holds state
608 * between invocations (for multiple-buffer loads). segp contains
609 * the segment following the starting one on entrace, and the ending
610 * segment on exit. first indicates if this is the first invocation
614 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
616 void *buf, bus_size_t buflen,
617 bus_dma_segment_t *segments,
621 vm_paddr_t *lastpaddrp,
626 vm_paddr_t paddr, nextpaddr;
627 bus_dma_segment_t *sg;
632 map = &nobounce_dmamap;
635 if (dmat->flags & BUS_DMA_ALIGNED)
636 KKASSERT(((uintptr_t)buf & (dmat->alignment - 1)) == 0);
640 * If we are being called during a callback, pagesneeded will
641 * be non-zero, so we can avoid doing the work twice.
643 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) &&
644 map != &nobounce_dmamap && map->pagesneeded == 0) {
645 vm_offset_t vendaddr;
648 * Count the number of bounce pages
649 * needed in order to complete this transfer
651 vaddr = (vm_offset_t)buf;
652 vendaddr = (vm_offset_t)buf + buflen;
654 while (vaddr < vendaddr) {
655 paddr = _bus_dma_extract(pmap, vaddr);
656 if (run_filter(dmat, paddr) != 0)
658 vaddr += (PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK));
662 /* Reserve Necessary Bounce Pages */
663 if (map->pagesneeded != 0) {
664 struct bounce_zone *bz;
666 bz = dmat->bounce_zone;
668 if (flags & BUS_DMA_NOWAIT) {
669 if (reserve_bounce_pages(dmat, map, 0) != 0) {
675 if (reserve_bounce_pages(dmat, map, 1) != 0) {
676 /* Queue us for resources */
679 map->buflen = buflen;
682 &dmat->bounce_zone->bounce_map_waitinglist,
686 return (EINPROGRESS);
692 KKASSERT(*segp >= 1 && *segp <= nsegments);
694 sg = &segments[seg - 1];
696 vaddr = (vm_offset_t)buf;
697 nextpaddr = *lastpaddrp;
698 bmask = ~(dmat->boundary - 1); /* note: will be 0 if boundary is 0 */
700 /* force at least one segment */
707 paddr = _bus_dma_extract(pmap, vaddr);
708 size = PAGE_SIZE - (paddr & PAGE_MASK);
711 if (map->pagesneeded != 0 && run_filter(dmat, paddr)) {
713 * note: this paddr has the same in-page offset
714 * as vaddr and thus the paddr above, so the
715 * size does not have to be recalculated
717 paddr = add_bounce_page(dmat, map, vaddr, size);
721 * Fill in the bus_dma_segment
727 } else if (paddr == nextpaddr) {
737 nextpaddr = paddr + size;
740 * Handle maxsegsz and boundary issues with a nested loop
746 * Limit to the boundary and maximum segment size
748 if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) {
749 tmpsize = dmat->boundary -
750 (sg->ds_addr & ~bmask);
751 if (tmpsize > dmat->maxsegsz)
752 tmpsize = dmat->maxsegsz;
753 KKASSERT(tmpsize < sg->ds_len);
754 } else if (sg->ds_len > dmat->maxsegsz) {
755 tmpsize = dmat->maxsegsz;
761 * Futz, split the data into a new segment.
763 if (seg >= nsegments)
765 sg[1].ds_len = sg[0].ds_len - tmpsize;
766 sg[1].ds_addr = sg[0].ds_addr + tmpsize;
767 sg[0].ds_len = tmpsize;
777 } while (buflen > 0);
783 *lastpaddrp = nextpaddr;
786 if (error && (dmat->flags & BUS_DMA_COULD_BOUNCE) &&
787 map != &nobounce_dmamap) {
788 _bus_dmamap_unload(dmat, map);
789 return_bounce_pages(dmat, map);
795 * Map the buffer buf into bus space using the dmamap map.
798 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
799 bus_size_t buflen, bus_dmamap_callback_t *callback,
800 void *callback_arg, int flags)
802 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
803 bus_dma_segment_t *segments;
804 vm_paddr_t lastaddr = 0;
805 int error, nsegs = 1;
810 * Follow old semantics. Once all of the callers are fixed,
811 * we should get rid of these internal flag "adjustment".
813 flags &= ~BUS_DMA_NOWAIT;
814 flags |= BUS_DMA_WAITOK;
816 map->callback = callback;
817 map->callback_arg = callback_arg;
820 segments = bus_dma_tag_lock(dmat, cache_segments);
821 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen,
822 segments, dmat->nsegments,
823 NULL, flags, &lastaddr, &nsegs, 1);
824 if (error == EINPROGRESS) {
825 bus_dma_tag_unlock(dmat);
828 callback(callback_arg, segments, nsegs, error);
829 bus_dma_tag_unlock(dmat);
834 * Like _bus_dmamap_load(), but for mbufs.
837 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
839 bus_dmamap_callback2_t *callback, void *callback_arg,
842 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
843 bus_dma_segment_t *segments;
848 * Follow old semantics. Once all of the callers are fixed,
849 * we should get rid of these internal flag "adjustment".
851 flags &= ~BUS_DMA_WAITOK;
852 flags |= BUS_DMA_NOWAIT;
854 segments = bus_dma_tag_lock(dmat, cache_segments);
855 error = bus_dmamap_load_mbuf_segment(dmat, map, m0,
856 segments, dmat->nsegments, &nsegs, flags);
858 /* force "no valid mappings" in callback */
859 callback(callback_arg, segments, 0,
862 callback(callback_arg, segments, nsegs,
863 m0->m_pkthdr.len, error);
865 bus_dma_tag_unlock(dmat);
870 bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat, bus_dmamap_t map,
872 bus_dma_segment_t *segs, int maxsegs,
873 int *nsegs, int flags)
879 KASSERT(maxsegs >= 1, ("invalid maxsegs %d\n", maxsegs));
880 KASSERT(maxsegs <= dmat->nsegments,
881 ("%d too many segments, dmat only support %d segments\n",
882 maxsegs, dmat->nsegments));
883 KASSERT(flags & BUS_DMA_NOWAIT,
884 ("only BUS_DMA_NOWAIT is supported\n"));
886 if (m0->m_pkthdr.len <= dmat->maxsize) {
888 vm_paddr_t lastaddr = 0;
893 for (m = m0; m != NULL && error == 0; m = m->m_next) {
897 error = _bus_dmamap_load_buffer(dmat, map,
900 NULL, flags, &lastaddr,
902 if (error == ENOMEM && !first) {
904 * Out of bounce pages due to too many
905 * fragments in the mbuf chain; return
914 KKASSERT(*nsegs <= maxsegs && *nsegs >= 1);
920 KKASSERT(error != EINPROGRESS);
925 * Like _bus_dmamap_load(), but for uios.
928 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
930 bus_dmamap_callback2_t *callback, void *callback_arg,
934 int nsegs, error, first, i;
938 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
939 bus_dma_segment_t *segments;
940 bus_dma_segment_t *segs;
943 if (dmat->nsegments <= BUS_DMA_CACHE_SEGMENTS)
944 segments = cache_segments;
946 segments = kmalloc(sizeof(bus_dma_segment_t) * dmat->nsegments,
947 M_DEVBUF, M_WAITOK | M_ZERO);
951 * Follow old semantics. Once all of the callers are fixed,
952 * we should get rid of these internal flag "adjustment".
954 flags &= ~BUS_DMA_WAITOK;
955 flags |= BUS_DMA_NOWAIT;
957 resid = (bus_size_t)uio->uio_resid;
961 nsegs_left = dmat->nsegments;
963 if (uio->uio_segflg == UIO_USERSPACE) {
967 KASSERT(td != NULL && td->td_proc != NULL,
968 ("bus_dmamap_load_uio: USERSPACE but no proc"));
969 pmap = vmspace_pmap(td->td_proc->p_vmspace);
978 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
980 * Now at the first iovec to load. Load each iovec
981 * until we have exhausted the residual count.
984 resid < iov[i].iov_len ? resid : iov[i].iov_len;
985 caddr_t addr = (caddr_t) iov[i].iov_base;
987 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen,
989 pmap, flags, &lastaddr, &nsegs, first);
1000 * Minimum one DMA segment, even if 0-length buffer.
1002 if (nsegs_left == dmat->nsegments)
1006 /* force "no valid mappings" in callback */
1007 callback(callback_arg, segments, 0,
1010 callback(callback_arg, segments, dmat->nsegments - nsegs_left,
1011 (bus_size_t)uio->uio_resid, error);
1013 if (dmat->nsegments > BUS_DMA_CACHE_SEGMENTS)
1014 kfree(segments, M_DEVBUF);
1019 * Release the mapping held by map.
1022 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
1024 struct bounce_page *bpage;
1026 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
1027 STAILQ_REMOVE_HEAD(&map->bpages, links);
1028 free_bounce_page(dmat, bpage);
1033 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
1035 struct bounce_page *bpage;
1037 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
1039 * Handle data bouncing. We might also
1040 * want to add support for invalidating
1041 * the caches on broken hardware
1044 case BUS_DMASYNC_PREWRITE:
1045 while (bpage != NULL) {
1046 bcopy((void *)bpage->datavaddr,
1047 (void *)bpage->vaddr,
1049 bpage = STAILQ_NEXT(bpage, links);
1051 dmat->bounce_zone->total_bounced++;
1054 case BUS_DMASYNC_POSTREAD:
1055 while (bpage != NULL) {
1056 bcopy((void *)bpage->vaddr,
1057 (void *)bpage->datavaddr,
1059 bpage = STAILQ_NEXT(bpage, links);
1061 dmat->bounce_zone->total_bounced++;
1064 case BUS_DMASYNC_PREREAD:
1065 case BUS_DMASYNC_POSTWRITE:
1073 alloc_bounce_zone(bus_dma_tag_t dmat)
1075 struct bounce_zone *bz, *new_bz;
1077 KASSERT(dmat->bounce_zone == NULL,
1078 ("bounce zone was already assigned\n"));
1080 new_bz = kmalloc(sizeof(*new_bz), M_DEVBUF, M_INTWAIT | M_ZERO);
1082 lwkt_gettoken(&bounce_zone_tok);
1084 /* Check to see if we already have a suitable zone */
1085 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1086 if (dmat->alignment <= bz->alignment &&
1087 dmat->lowaddr >= bz->lowaddr) {
1088 lwkt_reltoken(&bounce_zone_tok);
1090 dmat->bounce_zone = bz;
1091 kfree(new_bz, M_DEVBUF);
1098 spin_init(&bz->spin);
1100 STAILQ_INIT(&bz->bounce_page_list);
1101 STAILQ_INIT(&bz->bounce_map_waitinglist);
1102 bz->free_bpages = 0;
1103 bz->reserved_bpages = 0;
1104 bz->active_bpages = 0;
1105 bz->lowaddr = dmat->lowaddr;
1106 bz->alignment = round_page(dmat->alignment);
1107 ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1109 ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1110 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1112 lwkt_reltoken(&bounce_zone_tok);
1114 dmat->bounce_zone = bz;
1116 sysctl_ctx_init(&bz->sysctl_ctx);
1117 bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx,
1118 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1120 if (bz->sysctl_tree == NULL) {
1121 sysctl_ctx_free(&bz->sysctl_ctx);
1122 return 0; /* XXX error code? */
1125 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1126 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1127 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1128 "Total bounce pages");
1129 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1130 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1131 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1132 "Free bounce pages");
1133 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1134 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1135 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1136 "Reserved bounce pages");
1137 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1138 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1139 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1140 "Active bounce pages");
1141 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1142 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1143 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1144 "Total bounce requests");
1145 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1146 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1147 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1148 "Total bounce requests that were deferred");
1149 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1150 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1151 "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0,
1152 "Total bounce page reservations that were failed");
1153 SYSCTL_ADD_STRING(&bz->sysctl_ctx,
1154 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1155 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1156 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1157 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1158 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1164 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages, int flags)
1166 struct bounce_zone *bz = dmat->bounce_zone;
1167 int count = 0, mflags;
1169 if (flags & BUS_DMA_NOWAIT)
1174 while (numpages > 0) {
1175 struct bounce_page *bpage;
1177 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO);
1179 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1183 if (bpage->vaddr == 0) {
1184 kfree(bpage, M_DEVBUF);
1187 bpage->busaddr = pmap_kextract(bpage->vaddr);
1190 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1191 total_bounce_pages++;
1202 /* Assume caller holds bounce zone spinlock */
1204 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1206 struct bounce_zone *bz = dmat->bounce_zone;
1209 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1210 if (!commit && map->pagesneeded > (map->pagesreserved + pages)) {
1211 bz->reserve_failed++;
1212 return (map->pagesneeded - (map->pagesreserved + pages));
1215 bz->free_bpages -= pages;
1217 bz->reserved_bpages += pages;
1218 KKASSERT(bz->reserved_bpages <= bz->total_bpages);
1220 map->pagesreserved += pages;
1221 pages = map->pagesneeded - map->pagesreserved;
1227 return_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
1229 struct bounce_zone *bz = dmat->bounce_zone;
1230 int reserved = map->pagesreserved;
1231 bus_dmamap_t wait_map;
1233 map->pagesreserved = 0;
1234 map->pagesneeded = 0;
1241 bz->free_bpages += reserved;
1242 KKASSERT(bz->free_bpages <= bz->total_bpages);
1244 KKASSERT(bz->reserved_bpages >= reserved);
1245 bz->reserved_bpages -= reserved;
1247 wait_map = get_map_waiting(dmat);
1251 if (wait_map != NULL)
1252 add_map_callback(map);
1256 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1259 struct bounce_zone *bz = dmat->bounce_zone;
1260 struct bounce_page *bpage;
1262 KASSERT(map->pagesneeded > 0, ("map doesn't need any pages"));
1265 KASSERT(map->pagesreserved > 0, ("map doesn't reserve any pages"));
1266 map->pagesreserved--;
1270 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1271 KASSERT(bpage != NULL, ("free page list is empty"));
1272 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1274 KKASSERT(bz->reserved_bpages > 0);
1275 bz->reserved_bpages--;
1277 bz->active_bpages++;
1278 KKASSERT(bz->active_bpages <= bz->total_bpages);
1282 bpage->datavaddr = vaddr;
1283 bpage->datacount = size;
1284 STAILQ_INSERT_TAIL(&map->bpages, bpage, links);
1285 return bpage->busaddr;
1289 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1291 struct bounce_zone *bz = dmat->bounce_zone;
1294 bpage->datavaddr = 0;
1295 bpage->datacount = 0;
1299 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1302 KKASSERT(bz->free_bpages <= bz->total_bpages);
1304 KKASSERT(bz->active_bpages > 0);
1305 bz->active_bpages--;
1307 map = get_map_waiting(dmat);
1312 add_map_callback(map);
1315 /* Assume caller holds bounce zone spinlock */
1317 get_map_waiting(bus_dma_tag_t dmat)
1319 struct bounce_zone *bz = dmat->bounce_zone;
1322 map = STAILQ_FIRST(&bz->bounce_map_waitinglist);
1324 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1325 STAILQ_REMOVE_HEAD(&bz->bounce_map_waitinglist, links);
1326 bz->total_deferred++;
1335 add_map_callback(bus_dmamap_t map)
1337 /* XXX callbacklist is not MPSAFE */
1340 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, map, links);
1341 busdma_swi_pending = 1;
1353 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1354 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1356 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1357 map->callback, map->callback_arg, /*flags*/0);