exec.c: Record watchpoint fault address and direction

When we check whether we've hit a watchpoint we know the address
that we were attempting to access and whether it was a read or a
write. Record this information in the CPUWatchpoint struct so that
target-specific code can report it to the guest.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

exec.c

@@ -1673,7 +1673,12 @@ static void check_watchpoint(int offset, int len, int flags)
     QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
         if (cpu_watchpoint_address_matches(wp, vaddr, len)
             && (wp->flags & flags)) {
-            wp->flags |= BP_WATCHPOINT_HIT;
+            if (flags == BP_MEM_READ) {
+                wp->flags |= BP_WATCHPOINT_HIT_READ;
+            } else {
+                wp->flags |= BP_WATCHPOINT_HIT_WRITE;
+            }
+            wp->hitaddr = vaddr;
             if (!cpu->watchpoint_hit) {
                 cpu->watchpoint_hit = wp;
                 tb_check_watchpoint(cpu);

include/qom/cpu.h

@@ -170,6 +170,7 @@ typedef struct CPUBreakpoint {
 typedef struct CPUWatchpoint {
     vaddr vaddr;
     vaddr len;
+    vaddr hitaddr;
     int flags; /* BP_* */
     QTAILQ_ENTRY(CPUWatchpoint) entry;
 } CPUWatchpoint;
@@ -622,9 +623,12 @@ void cpu_single_step(CPUState *cpu, int enabled);
 #define BP_MEM_WRITE          0x02
 #define BP_MEM_ACCESS         (BP_MEM_READ | BP_MEM_WRITE)
 #define BP_STOP_BEFORE_ACCESS 0x04
-#define BP_WATCHPOINT_HIT     0x08
+/* 0x08 currently unused */
 #define BP_GDB                0x10
 #define BP_CPU                0x20
+#define BP_WATCHPOINT_HIT_READ 0x40
+#define BP_WATCHPOINT_HIT_WRITE 0x80
+#define BP_WATCHPOINT_HIT (BP_WATCHPOINT_HIT_READ | BP_WATCHPOINT_HIT_WRITE)
 
 int cpu_breakpoint_insert(CPUState *cpu, vaddr pc, int flags,
                           CPUBreakpoint **breakpoint);