freebsd-dev/sys/dev/hyperv/vmbus/hyperv_busdma.c
Sepherosa Ziehau d8313c45a6 hyperv/busdma: Take BUS_DMA_ZERO into account
MFC after:	1 week
Sponsored by:	Microsoft OSTC
Differential Revision:	https://reviews.freebsd.org/D6499
2016-05-24 05:26:52 +00:00

99 lines
3.0 KiB
C

/*-
* Copyright (c) 2016 Microsoft Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <dev/hyperv/include/hyperv_busdma.h>
#define HYPERV_DMA_MASK (BUS_DMA_WAITOK | BUS_DMA_NOWAIT | BUS_DMA_ZERO)
void
hyperv_dma_map_paddr(void *arg, bus_dma_segment_t *segs, int nseg, int error)
{
bus_addr_t *paddr = arg;
if (error)
return;
KASSERT(nseg == 1, ("too many segments %d!", nseg));
*paddr = segs->ds_addr;
}
void *
hyperv_dmamem_alloc(bus_dma_tag_t parent_dtag, bus_size_t alignment,
bus_addr_t boundary, bus_size_t size, struct hyperv_dma *dma, int flags)
{
void *ret;
int error;
error = bus_dma_tag_create(parent_dtag, /* parent */
alignment, /* alignment */
boundary, /* boundary */
BUS_SPACE_MAXADDR, /* lowaddr */
BUS_SPACE_MAXADDR, /* highaddr */
NULL, NULL, /* filter, filterarg */
size, /* maxsize */
1, /* nsegments */
size, /* maxsegsize */
0, /* flags */
NULL, /* lockfunc */
NULL, /* lockfuncarg */
&dma->hv_dtag);
if (error)
return NULL;
error = bus_dmamem_alloc(dma->hv_dtag, &ret,
(flags & HYPERV_DMA_MASK) | BUS_DMA_COHERENT, &dma->hv_dmap);
if (error) {
bus_dma_tag_destroy(dma->hv_dtag);
return NULL;
}
error = bus_dmamap_load(dma->hv_dtag, dma->hv_dmap, ret, size,
hyperv_dma_map_paddr, &dma->hv_paddr, BUS_DMA_NOWAIT);
if (error) {
bus_dmamem_free(dma->hv_dtag, ret, dma->hv_dmap);
bus_dma_tag_destroy(dma->hv_dtag);
return NULL;
}
return ret;
}
void
hyperv_dmamem_free(struct hyperv_dma *dma, void *ptr)
{
bus_dmamap_unload(dma->hv_dtag, dma->hv_dmap);
bus_dmamem_free(dma->hv_dtag, ptr, dma->hv_dmap);
bus_dma_tag_destroy(dma->hv_dtag);
}