Sync bus_dmamap_load_raw() with amd64 for better constraint checking.

Needed by xhci(4).

diff --git a/sys/arch/octeon/octeon/bus_dma.c b/sys/arch/octeon/octeon/bus_dma.c
index 09d8553..5c14b45 100644 (file)
--- a/sys/arch/octeon/octeon/bus_dma.c
+++ b/sys/arch/octeon/octeon/bus_dma.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: bus_dma.c,v 1.14 2014/11/16 12:30:58 deraadt Exp $ */
+/*     $OpenBSD: bus_dma.c,v 1.15 2017/04/15 04:38:27 visa Exp $ */
 
 /*
  * Copyright (c) 2003-2004 Opsycon AB  (www.opsycon.se / www.opsycon.com)
@@ -256,30 +256,82 @@ int
 _dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map, bus_dma_segment_t *segs,
     int nsegs, bus_size_t size, int flags)
 {
-       if (nsegs > map->_dm_segcnt || size > map->_dm_size)
-               return (EINVAL);
+       bus_addr_t paddr, baddr, bmask, lastaddr = 0;
+       bus_size_t plen, sgsize, mapsize;
+       int first = 1;
+       int i, seg = 0;
 
        /*
-        * Make sure we don't cross any boundaries.
+        * Make sure that on error condition we return "no valid mappings".
         */
-       if (map->_dm_boundary) {
-               bus_addr_t bmask = ~(map->_dm_boundary - 1);
-               int i;
-
-               if (t->_dma_mask != 0)
-                       bmask &= t->_dma_mask;
-               for (i = 0; i < nsegs; i++) {
-                       if (segs[i].ds_len > map->_dm_maxsegsz)
-                               return (EINVAL);
-                       if ((segs[i].ds_addr & bmask) !=
-                           ((segs[i].ds_addr + segs[i].ds_len - 1) & bmask))
-                               return (EINVAL);
+       map->dm_mapsize = 0;
+       map->dm_nsegs = 0;
+
+       if (nsegs > map->_dm_segcnt || size > map->_dm_size)
+               return (EINVAL);
+
+       mapsize = size;
+       bmask = ~(map->_dm_boundary - 1);
+
+       for (i = 0; i < nsegs && size > 0; i++) {
+               paddr = segs[i].ds_addr;
+               plen = MIN(segs[i].ds_len, size);
+
+               while (plen > 0) {
+                       /*
+                        * Compute the segment size, and adjust counts.
+                        */
+                       sgsize = PAGE_SIZE - ((u_long)paddr & PGOFSET);
+                       if (plen < sgsize)
+                               sgsize = plen;
+
+                       if (paddr > dma_constraint.ucr_high)
+                               panic("Non dma-reachable buffer at "
+                                   "paddr %#lx(raw)", paddr);
+
+                       /*
+                        * Make sure we don't cross any boundaries.
+                        */
+                       if (map->_dm_boundary > 0) {
+                               baddr = (paddr + map->_dm_boundary) & bmask;
+                               if (sgsize > (baddr - paddr))
+                                       sgsize = (baddr - paddr);
+                       }
+
+                       /*
+                        * Insert chunk into a segment, coalescing with
+                        * previous segment if possible.
+                        */
+                       if (first) {
+                               map->dm_segs[seg].ds_addr = paddr;
+                               map->dm_segs[seg].ds_len = sgsize;
+                               first = 0;
+                       } else {
+                               if (paddr == lastaddr &&
+                                   (map->dm_segs[seg].ds_len + sgsize) <=
+                                    map->_dm_maxsegsz &&
+                                   (map->_dm_boundary == 0 ||
+                                    (map->dm_segs[seg].ds_addr & bmask) ==
+                                    (paddr & bmask)))
+                                       map->dm_segs[seg].ds_len += sgsize;
+                               else {
+                                       if (++seg >= map->_dm_segcnt)
+                                               return (EINVAL);
+                                       map->dm_segs[seg].ds_addr = paddr;
+                                       map->dm_segs[seg].ds_len = sgsize;
+                               }
+                       }
+
+                       paddr += sgsize;
+                       plen -= sgsize;
+                       size -= sgsize;
+
+                       lastaddr = paddr;
                }
        }
 
-       bcopy(segs, map->dm_segs, nsegs * sizeof(*segs));
-       map->dm_nsegs = nsegs;
-       map->dm_mapsize = size;
+       map->dm_mapsize = mapsize;
+       map->dm_nsegs = seg + 1;
        return (0);
 }