support uncachable on-demand mapping

kernel/include/process.h

@@ -41,6 +41,9 @@
 #define	VR_MAXPROT_WRITE   0x00200000
 #define	VR_MAXPROT_EXEC    0x00400000
 #define	VR_MAXPROT_MASK    0x00700000
+#define	VR_MEMTYPE_WB      0x00000000	/* write-back */
+#define	VR_MEMTYPE_UC      0x01000000	/* uncachable */
+#define	VR_MEMTYPE_MASK    0x0f000000
 
 #define	PROT_TO_VR_FLAG(prot)	(((unsigned long)(prot) << 16) & VR_PROT_MASK)
 #define	VRFLAG_PROT_TO_MAXPROT(vrflag)	(((vrflag) & VR_PROT_MASK) << 4)

kernel/process.c

@@ -791,6 +791,10 @@ enum ihk_mc_pt_attribute common_vrflag_to_ptattr(unsigned long flag, uint64_t fa
 		attr |= PTATTR_NO_EXECUTE;
 	}
 
+	if ((flag & VR_MEMTYPE_MASK) == VR_MEMTYPE_UC) {
+		attr |= PTATTR_UNCACHABLE;
+	}
+
 	return attr;
 }