Basic VM and other minor improvements.

Not complete, probably not fully debugged or optimized.

kernel/arch/i386/include/archconst.h

@@ -135,12 +135,6 @@
 #define IF_MASK 0x00000200
 #define IOPL_MASK 0x003000
 
-/* Sizes of memory tables. The boot monitor distinguishes three memory areas,
- * namely low mem below 1M, 1M-16M, and mem after 16M. More chunks are needed
- * for DOS MINIX.
- */
-#define NR_MEMS            8
-
 #define vir2phys(vir)   (kinfo.data_base + (vir_bytes) (vir))
 
 #endif /* _I386_ACONST_H */

kernel/arch/i386/include/archtypes.h

@@ -55,8 +55,18 @@ struct segdesc_s {		/* segment descriptor for protected mode */
 
 typedef struct segframe {
 	reg_t p_ldt_sel;    /* selector in gdt with ldt base and limit */
+	reg_t	p_cr3;		/* page table root */
 	struct segdesc_s p_ldt[2+NR_REMOTE_SEGS]; /* CS, DS and remote */
 } segframe_t;
 
+/* Page fault event. Stored in process table. Only valid if PAGEFAULT
+ * set in p_rts_flags.
+ */
+struct pagefault
+{
+	u32_t   pf_virtual;     /* Address causing fault (CR2). */
+	u32_t   pf_flags;       /* Pagefault flags on stack. */
+};
+
 #endif /* #ifndef _I386_TYPES_H */