sys/dev/virtual/hyperv/vmbus/hyperv_busdma.c

   1 /*-
   2  * Copyright (c) 2016 Microsoft Corp.
   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 unmodified, this list of conditions, and the following
  10  *    disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include <sys/param.h>
  28 #include <sys/systm.h>
  29 #include <sys/bus.h>
  30
  31 #include <dev/virtual/hyperv/include/hyperv_busdma.h>
  32
  33 void
  34 hyperv_dma_map_paddr(void *arg, bus_dma_segment_t *segs, int nseg, int error)
  35 {
  36         bus_addr_t *paddr = arg;
  37
  38         if (error)
  39                 return;
  40
  41         KASSERT(nseg == 1, ("too many segments %d!", nseg));
  42         *paddr = segs->ds_addr;
  43 }
  44
  45 void *
  46 hyperv_dmamem_alloc(bus_dma_tag_t parent_dtag, bus_size_t alignment,
  47     bus_addr_t boundary, bus_size_t size, struct hyperv_dma *dma, int flags)
  48 {
  49         bus_dmamem_t dmem;
  50         int error;
  51
  52         error = bus_dmamem_coherent(parent_dtag, alignment, boundary,
  53             BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, size, flags, &dmem);
  54         if (error)
  55                 return NULL;
  56
  57         dma->hv_dtag = dmem.dmem_tag;
  58         dma->hv_dmap = dmem.dmem_map;
  59         dma->hv_paddr = dmem.dmem_busaddr;
  60         return dmem.dmem_addr;
  61 }
  62
  63 void
  64 hyperv_dmamem_free(struct hyperv_dma *dma, void *ptr)
  65 {
  66         bus_dmamap_unload(dma->hv_dtag, dma->hv_dmap);
  67         bus_dmamem_free(dma->hv_dtag, ptr, dma->hv_dmap);
  68         bus_dma_tag_destroy(dma->hv_dtag);
  69 }