PERFORCE change 54806 for review

[Juli Mallett]

http://perforce.freebsd.org/chv.cgi?CH=54806

Change 54806 by jmallett at jmallett_oingo on 2004/06/13 09:47:51

	Add check_address(), which is an NIHBSD compatible function to NetBSD's
	badvaddr(), but it doesn't do alignment.  Most things can do that for
	themselves.  At least ISTR badvaddr() checks int alignment.
	
	Use check_address() in HPC ala NetBSD.
	
	Next year, resolve to ramble less in commit/submit messages.

Affected files ...

.. //depot/projects/mips/sys/mips/include/trap.h#5 edit
.. //depot/projects/mips/sys/mips/mips/trap.c#21 edit
.. //depot/projects/mips/sys/mips/sgimips/hpc/hpc.c#3 edit

Differences ...

==== //depot/projects/mips/sys/mips/include/trap.h#5 (text+ko) ====

@@ -50,6 +50,10 @@
 #define	TrVCED		31
 
 #ifndef LOCORE /* XXX */
+struct trapframe;
+
+void trap(struct trapframe *, u_int, void *);
+int check_address(void *);
 void platform_trap_enter(void);
 void platform_trap_exit(void);
 #endif

==== //depot/projects/mips/sys/mips/mips/trap.c#21 (text+ko) ====

@@ -34,6 +34,7 @@
 
 #include <vm/vm.h>
 #include <vm/pmap.h>
+#include <vm/vm_map.h>
 
 #include <machine/cpu.h>
 #include <machine/frame.h>
@@ -86,8 +87,9 @@
 };
 #define	MAXTRAPID	31
 
-/* XXX belongs in a header some day? */
-void trap(struct trapframe *, u_int, void *);
+/* Protected by critical sections, for checking for bad addresses.  */
+static char *trap_addr;
+static int trap_error;
 
 void
 trap(struct trapframe *tf, u_int cause, void *badvaddr)
@@ -99,7 +101,7 @@
 
 	code = (cause & MIPS_CR_EXC_CODE) >> MIPS_CR_EXC_CODE_SHIFT;
 	kernelmode = (tf->tf_regs[TF_SR] & MIPS_SR_KSU_USER) == 0;
-	
+
 	if (curthread != NULL)
 		bcopy(tf, curthread->td_frame, sizeof *tf);
 
@@ -115,6 +117,13 @@
 		/*platform_trap_exit();*/
 		platform_intr(tf);
 		goto done;
+	case TrAdEL:
+		if (trap_error == -1) {
+			if (trap_addr == badvaddr)
+				trap_error = EINVAL;
+			goto done;
+		}
+		/* fall through */
 	default:
 		/* Fatal! */
 		break;
@@ -173,3 +182,25 @@
 	if (curthread)
 		bcopy(curthread->td_frame, tf, sizeof *tf);
 }
+
+int
+check_address(void *addr)
+{
+	vm_paddr_t pa;
+	char b;
+	int error;
+
+	critical_enter();
+	pa = pmap_kextract((vm_offset_t)addr);
+	trap_addr = (char *)MIPS_PHYS_TO_KSEG1(pa);
+	trap_error = -1;
+	b = *trap_addr;
+	trap_addr = NULL;
+	error = trap_error;
+	trap_error = 0;
+	critical_exit();
+
+	if (error == -1)
+		return (0);
+	return (error);
+}

==== //depot/projects/mips/sys/mips/sgimips/hpc/hpc.c#3 (text+ko) ====

@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $P4: //depot/projects/mips/sys/mips/sgimips/hpc/hpc.c#2 $
+ * $P4: //depot/projects/mips/sys/mips/sgimips/hpc/hpc.c#3 $
  */
 
 #include <sys/cdefs.h>
@@ -36,6 +36,7 @@
 #include <sys/bus.h>
 
 #include <machine/bus.h>
+#include <machine/trap.h>
 #include <platform/models.h>
 
 static devclass_t hpc_devclass;
@@ -92,6 +93,10 @@
 					    "port", &port);
 		if (error != 0)
 			return (ENODEV);
+		/* XXX circumvents resource_long_value() */
+		error = check_address((void *)MIPS_PHYS_TO_KSEG1(port));
+		if (error != 0)
+			return (error);
 		sc->sc_tag = device_space_tag;
 		sc->sc_handle = port;
 		return (0);