[Qemu-devel] [RFC v6 03/14] Add CPUClass hook to set exclusive range

[Alvise Rigo]

Allow each architecture to set the exclusive range at any LoadLink
operation through a CPUClass hook.
This comes in handy to emulate, for instance, the exclusive monitor
implemented in some ARM architectures (more precisely, the Exclusive
Reservation Granule).

Suggested-by: Jani Kokkonen <address@hidden>
Suggested-by: Claudio Fontana <address@hidden>
Signed-off-by: Alvise Rigo <address@hidden>
---
 include/qom/cpu.h | 4 ++++
 qom/cpu.c         | 7 +++++++
 2 files changed, 11 insertions(+)

diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index c6bb6b6..9e409ce 100644
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -175,6 +175,10 @@ typedef struct CPUClass {
     void (*cpu_exec_exit)(CPUState *cpu);
     bool (*cpu_exec_interrupt)(CPUState *cpu, int interrupt_request);
 
+    /* Atomic instruction handling */
+    void (*cpu_set_excl_protected_range)(CPUState *cpu, hwaddr addr,
+                                         hwaddr size);
+
     void (*disas_set_info)(CPUState *cpu, disassemble_info *info);
 } CPUClass;
 
diff --git a/qom/cpu.c b/qom/cpu.c
index fb80d13..a5c25a8 100644
--- a/qom/cpu.c
+++ b/qom/cpu.c
@@ -203,6 +203,12 @@ static bool cpu_common_exec_interrupt(CPUState *cpu, int 
int_req)
     return false;
 }
 
+static void cpu_common_set_excl_range(CPUState *cpu, hwaddr addr, hwaddr size)
+{
+    cpu->excl_protected_range.begin = addr;
+    cpu->excl_protected_range.end = addr + size;
+}
+
 void cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
                     int flags)
 {
@@ -355,6 +361,7 @@ static void cpu_class_init(ObjectClass *klass, void *data)
     k->cpu_exec_enter = cpu_common_noop;
     k->cpu_exec_exit = cpu_common_noop;
     k->cpu_exec_interrupt = cpu_common_exec_interrupt;
+    k->cpu_set_excl_protected_range = cpu_common_set_excl_range;
     dc->realize = cpu_common_realizefn;
     /*
      * Reason: CPUs still need special care by board code: wiring up
-- 
2.6.4