xnu-1699.26.8.tar.gz

[apple/xnu.git] / osfmk / i386 / phys.c

diff --git a/osfmk/i386/phys.c b/osfmk/i386/phys.c
index c8a2f520653b56a3f789966d5e17a79e3df498e9..bfbb48d4ba6243ce5119ae37cf2d14004edc8dd5 100644 (file)
--- a/osfmk/i386/phys.c
+++ b/osfmk/i386/phys.c
@@ -229,6 +229,9 @@ kvtophys(
        return ((addr64_t)pa);
 }
 
+extern pt_entry_t *debugger_ptep;
+extern vm_map_offset_t debugger_window_kva;
+
 __private_extern__ void ml_copy_phys(addr64_t src64, addr64_t dst64, vm_size_t bytes) {
        void *src, *dst;
 
@@ -243,6 +246,36 @@ __private_extern__ void ml_copy_phys(addr64_t src64, addr64_t dst64, vm_size_t b
 #elif defined(__x86_64__)
        src = PHYSMAP_PTOV(src64);
        dst = PHYSMAP_PTOV(dst64);
+
+       addr64_t debug_pa = 0;
+
+       /* If either destination or source are outside the
+        * physical map, establish a physical window onto the target frame.
+        */
+       assert(physmap_enclosed(src64) || physmap_enclosed(dst64));
+
+       if (physmap_enclosed(src64) == FALSE) {
+               src = (void *)(debugger_window_kva | (src64 & INTEL_OFFMASK));
+               debug_pa = src64 & PG_FRAME;
+       } else if (physmap_enclosed(dst64) == FALSE) {
+               dst = (void *)(debugger_window_kva | (dst64 & INTEL_OFFMASK));
+               debug_pa = dst64 & PG_FRAME;
+       }
+       /* DRK: debugger only routine, we don't bother checking for an
+        * identical mapping.
+        */
+       if (debug_pa) {
+               if (debugger_window_kva == 0)
+                       panic("%s: invoked in non-debug mode", __FUNCTION__);
+               /* Establish a cache-inhibited physical window; some platforms
+                * may not cover arbitrary ranges with MTRRs
+                */
+               pmap_store_pte(debugger_ptep, debug_pa | INTEL_PTE_NCACHE | INTEL_PTE_RW | INTEL_PTE_REF| INTEL_PTE_MOD | INTEL_PTE_VALID);
+               flush_tlb_raw();
+#if    DEBUG
+               kprintf("Remapping debugger physical window at %p to 0x%llx\n", (void *)debugger_window_kva, debug_pa);
+#endif
+       }
 #endif
        /* ensure we stay within a page */
        if (((((uint32_t)src64 & (I386_PGBYTES-1)) + bytes) > I386_PGBYTES) || ((((uint32_t)dst64 & (I386_PGBYTES-1)) + bytes) > I386_PGBYTES) ) {
@@ -251,17 +284,17 @@ __private_extern__ void ml_copy_phys(addr64_t src64, addr64_t dst64, vm_size_t b
 
        switch (bytes) {
        case 1:
-               *((uint8_t *) dst) = *((uint8_t *) src);
+               *((uint8_t *) dst) = *((volatile uint8_t *) src);
                break;
        case 2:
-               *((uint16_t *) dst) = *((uint16_t *) src);
+               *((uint16_t *) dst) = *((volatile uint16_t *) src);
                break;
        case 4:
-               *((uint32_t *) dst) = *((uint32_t *) src);
+               *((uint32_t *) dst) = *((volatile uint32_t *) src);
                break;
                /* Should perform two 32-bit reads */
        case 8:
-               *((uint64_t *) dst) = *((uint64_t *) src);
+               *((uint64_t *) dst) = *((volatile uint64_t *) src);
                break;
        default:
                bcopy(src, dst, bytes);