svn commit: r303605 - head/sys/dev/hyperv/storvsc

[Sepherosa Ziehau]

Author: sephe
Date: Mon Aug  1 05:09:11 2016
New Revision: 303605
URL: https://svnweb.freebsd.org/changeset/base/303605

Log:
  hyperv/storvsc: Stringent PRP list assertions
  
  MFC after:	1 week
  Sponsored by:	Microsoft
  Differential Revision:	https://reviews.freebsd.org/D7361

Modified:
  head/sys/dev/hyperv/storvsc/hv_storvsc_drv_freebsd.c

Modified: head/sys/dev/hyperv/storvsc/hv_storvsc_drv_freebsd.c
==============================================================================
--- head/sys/dev/hyperv/storvsc/hv_storvsc_drv_freebsd.c	Mon Aug  1 04:51:31 2016	(r303604)
+++ head/sys/dev/hyperv/storvsc/hv_storvsc_drv_freebsd.c	Mon Aug  1 05:09:11 2016	(r303605)
@@ -1775,13 +1775,28 @@ storvsc_xferbuf_prepare(void *arg, bus_d
 	prplist->gpa_range.gpa_ofs = segs[0].ds_addr & PAGE_MASK;
 
 	for (i = 0; i < nsegs; i++) {
-		prplist->gpa_page[i] = atop(segs[i].ds_addr);
 #ifdef INVARIANTS
-		if (i != 0 && i != nsegs - 1) {
-			KASSERT((segs[i].ds_addr & PAGE_MASK) == 0 &&
-			    segs[i].ds_len == PAGE_SIZE, ("not a full page"));
+		if (nsegs > 1) {
+			if (i == 0) {
+				KASSERT((segs[i].ds_addr & PAGE_MASK) +
+				    segs[i].ds_len == PAGE_SIZE,
+				    ("invalid 1st page, ofs 0x%jx, len %zu",
+				     (uintmax_t)segs[i].ds_addr,
+				     segs[i].ds_len));
+			} else if (i == nsegs - 1) {
+				KASSERT((segs[i].ds_addr & PAGE_MASK) == 0,
+				    ("invalid last page, ofs 0x%jx",
+				     (uintmax_t)segs[i].ds_addr));
+			} else {
+				KASSERT((segs[i].ds_addr & PAGE_MASK) == 0 &&
+				    segs[i].ds_len == PAGE_SIZE,
+				    ("not a full page, ofs 0x%jx, len %zu",
+				     (uintmax_t)segs[i].ds_addr,
+				     segs[i].ds_len));
+			}
 		}
 #endif
+		prplist->gpa_page[i] = atop(segs[i].ds_addr);
 	}
 	reqp->prp_cnt = nsegs;
 }