[Qemu-devel] [6601] qemu: add cpu_unregister_io_memory and make io mem table index dynamic ( Marcelo Tosatti)

[Qemu-devel] [6601] qemu: add cpu_unregister_io_memory and make io mem table index dynamic ( Marcelo Tosatti)

[Anthony Liguori]

Revision: 6601
          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6601
Author:   aliguori
Date:     2009-02-11 15:20:58 +0000 (Wed, 11 Feb 2009)

Log Message:
-----------
qemu: add cpu_unregister_io_memory and make io mem table index dynamic (Marcelo Tosatti)

So drivers can clear their mem io table entries on exit back to unassigned
state.

Also make the io mem index allocation dynamic.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

Modified Paths:
--------------
    trunk/cpu-all.h
    trunk/exec.c

Modified: trunk/cpu-all.h
===================================================================
--- trunk/cpu-all.h	2009-02-11 15:20:51 UTC (rev 6600)
+++ trunk/cpu-all.h	2009-02-11 15:20:58 UTC (rev 6601)
@@ -909,6 +909,7 @@
                            CPUReadMemoryFunc **mem_read,
                            CPUWriteMemoryFunc **mem_write,
                            void *opaque);
+void cpu_unregister_io_memory(int table_address);
 CPUWriteMemoryFunc **cpu_get_io_memory_write(int io_index);
 CPUReadMemoryFunc **cpu_get_io_memory_read(int io_index);
 

Modified: trunk/exec.c
===================================================================
--- trunk/exec.c	2009-02-11 15:20:51 UTC (rev 6600)
+++ trunk/exec.c	2009-02-11 15:20:58 UTC (rev 6601)
@@ -179,7 +179,7 @@
 CPUWriteMemoryFunc *io_mem_write[IO_MEM_NB_ENTRIES][4];
 CPUReadMemoryFunc *io_mem_read[IO_MEM_NB_ENTRIES][4];
 void *io_mem_opaque[IO_MEM_NB_ENTRIES];
-static int io_mem_nb;
+char io_mem_used[IO_MEM_NB_ENTRIES];
 static int io_mem_watch;
 #endif
 
@@ -2799,12 +2799,28 @@
     return mmio;
 }
 
+static int get_free_io_mem_idx(void)
+{
+    int i;
+
+    for (i = 0; i<IO_MEM_NB_ENTRIES; i++)
+        if (!io_mem_used[i]) {
+            io_mem_used[i] = 1;
+            return i;
+        }
+
+    return -1;
+}
+
 static void io_mem_init(void)
 {
+    int i;
+
     cpu_register_io_memory(IO_MEM_ROM >> IO_MEM_SHIFT, error_mem_read, unassigned_mem_write, NULL);
     cpu_register_io_memory(IO_MEM_UNASSIGNED >> IO_MEM_SHIFT, unassigned_mem_read, unassigned_mem_write, NULL);
     cpu_register_io_memory(IO_MEM_NOTDIRTY >> IO_MEM_SHIFT, error_mem_read, notdirty_mem_write, NULL);
-    io_mem_nb = 5;
+    for (i=0; i<5; i++)
+        io_mem_used[i] = 1;
 
     io_mem_watch = cpu_register_io_memory(0, watch_mem_read,
                                           watch_mem_write, NULL);
@@ -2829,9 +2845,9 @@
     int i, subwidth = 0;
 
     if (io_index <= 0) {
-        if (io_mem_nb >= IO_MEM_NB_ENTRIES)
-            return -1;
-        io_index = io_mem_nb++;
+        io_index = get_free_io_mem_idx();
+        if (io_index == -1)
+            return io_index;
     } else {
         if (io_index >= IO_MEM_NB_ENTRIES)
             return -1;
@@ -2847,6 +2863,19 @@
     return (io_index << IO_MEM_SHIFT) | subwidth;
 }
 
+void cpu_unregister_io_memory(int io_table_address)
+{
+    int i;
+    int io_index = io_table_address >> IO_MEM_SHIFT;
+
+    for (i=0;i < 3; i++) {
+        io_mem_read[io_index][i] = unassigned_mem_read[i];
+        io_mem_write[io_index][i] = unassigned_mem_write[i];
+    }
+    io_mem_opaque[io_index] = NULL;
+    io_mem_used[io_index] = 0;
+}
+
 CPUWriteMemoryFunc **cpu_get_io_memory_write(int io_index)
 {
     return io_mem_write[io_index >> IO_MEM_SHIFT];