xnu-1699.26.8.tar.gz

[apple/xnu.git] / osfmk / kdp / ml / i386 / kdp_x86_common.c

diff --git a/osfmk/kdp/ml/i386/kdp_x86_common.c b/osfmk/kdp/ml/i386/kdp_x86_common.c
index 221d683ac7b2d9c5f84f266b83cbb1a83a432e48..6016e48353b44f3bc058da235f1243f57014f47e 100644 (file)
--- a/osfmk/kdp/ml/i386/kdp_x86_common.c
+++ b/osfmk/kdp/ml/i386/kdp_x86_common.c
@@ -38,6 +38,8 @@
 #include <i386/pio.h>
 #include <i386/proc_reg.h>
 
+#include <i386/pmap_internal.h>
+
 #include <kdp/kdp_internal.h>
 #include <mach/vm_map.h>
 
@@ -374,3 +376,36 @@ kdp_machine_msr64_write(kdp_writemsr64_req_t *rq, caddr_t data, uint16_t lcpu)
        wrmsr64(msr, *value);
        return KDPERR_NO_ERROR;
 }
+
+pt_entry_t *debugger_ptep;
+vm_map_offset_t debugger_window_kva;
+
+/* Establish a pagetable window that can be remapped on demand.
+ * This is utilized by the debugger to address regions outside
+ * the physical map.
+ */
+
+void
+kdp_machine_init(void) {
+       if (debug_boot_arg == 0)
+               return;
+
+       vm_map_entry_t e;
+       kern_return_t kr = vm_map_find_space(kernel_map,
+           &debugger_window_kva,
+           PAGE_SIZE, 0,
+           VM_MAKE_TAG(VM_MEMORY_IOKIT), &e);
+
+       if (kr != KERN_SUCCESS) {
+               panic("%s: vm_map_find_space failed with %d\n", __FUNCTION__, kr);
+       }
+
+       vm_map_unlock(kernel_map);
+
+       debugger_ptep = pmap_pte(kernel_pmap, debugger_window_kva);
+
+       if (debugger_ptep == NULL) {
+               pmap_expand(kernel_pmap, debugger_window_kva);
+               debugger_ptep = pmap_pte(kernel_pmap, debugger_window_kva);
+       }
+}