svn commit: r276600 - in head/sys/amd64: amd64 include

[Konstantin Belousov]

Author: kib
Date: Sat Jan  3 01:28:58 2015
New Revision: 276600
URL: https://svnweb.freebsd.org/changeset/base/276600

Log:
  For /dev/mem and /dev/kmem accesses, avoid asserting that addresses
  are within direct map.  We want to return error instead of panicing.
  
  PR:	194995
  Sponsored by:	The FreeBSD Foundation

Modified:
  head/sys/amd64/amd64/mem.c
  head/sys/amd64/include/vmparam.h

Modified: head/sys/amd64/amd64/mem.c
==============================================================================
--- head/sys/amd64/amd64/mem.c	Sat Jan  3 00:31:52 2015	(r276599)
+++ head/sys/amd64/amd64/mem.c	Sat Jan  3 01:28:58 2015	(r276600)
@@ -98,7 +98,7 @@ memrw(struct cdev *dev, struct uio *uio,
 kmemphys:
 			o = v & PAGE_MASK;
 			c = min(uio->uio_resid, (u_int)(PAGE_SIZE - o));
-			vd = PHYS_TO_DMAP(v);
+			vd = PHYS_TO_DMAP_RAW(v);
 			if (vd < DMAP_MIN_ADDRESS ||
 			    (vd > DMAP_MIN_ADDRESS + dmaplimit &&
 			    vd <= DMAP_MAX_ADDRESS) ||
@@ -112,7 +112,7 @@ kmemphys:
 			v = uio->uio_offset;
 
 			if (v >= DMAP_MIN_ADDRESS && v < DMAP_MAX_ADDRESS) {
-				v = DMAP_TO_PHYS(v);
+				v = DMAP_TO_PHYS_RAW(v);
 				goto kmemphys;
 			}
 

Modified: head/sys/amd64/include/vmparam.h
==============================================================================
--- head/sys/amd64/include/vmparam.h	Sat Jan  3 00:31:52 2015	(r276599)
+++ head/sys/amd64/include/vmparam.h	Sat Jan  3 01:28:58 2015	(r276600)
@@ -183,6 +183,8 @@
 #define	VM_MAX_ADDRESS		UPT_MAX_ADDRESS
 #define	VM_MIN_ADDRESS		(0)
 
+#define	PHYS_TO_DMAP_RAW(x)	((x) | DMAP_MIN_ADDRESS)
+#define	DMAP_TO_PHYS_RAW(x)	((x) & ~DMAP_MIN_ADDRESS)
 /*
  * XXX Allowing dmaplimit == 0 is a temporary workaround for vt(4) efifb's
  * early use of PHYS_TO_DMAP before the mapping is actually setup. This works
@@ -193,14 +195,14 @@
 	KASSERT(dmaplimit == 0 || (x) < dmaplimit,			\
 	    ("physical address %#jx not covered by the DMAP",		\
 	    (uintmax_t)x));						\
-	(x) | DMAP_MIN_ADDRESS; })
+	PHYS_TO_DMAP_RAW(x); })
 
 #define	DMAP_TO_PHYS(x)	({						\
 	KASSERT((x) < (DMAP_MIN_ADDRESS + dmaplimit) &&			\
 	    (x) >= DMAP_MIN_ADDRESS,					\
 	    ("virtual address %#jx not covered by the DMAP",		\
 	    (uintmax_t)x));						\
-	(x) & ~DMAP_MIN_ADDRESS; })
+	DMAP_TO_PHYS_RAW(x); })
 
 /*
  * How many physical pages per kmem arena virtual page.