Use virtual memory to allocate g_mem_base (if possible).

mupen64plus · Nov 5, 2017 · 3d7f6c4 · 3d7f6c4
1 parent 8964997
commit 3d7f6c4
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Showing 4 changed files with 88 additions and 2 deletions.
diff --git a/projects/unix/Makefile b/projects/unix/Makefile
@@ -160,6 +160,7 @@ endif
 ifeq ($(OS), FREEBSD)
   TARGET = libmupen64plus$(POSTFIX).so.2.0.0
   SONAME = libmupen64plus$(POSTFIX).so.2
+  CFLAGS += -DHAVE_MMAP
   LDFLAGS += -Wl,-Bsymbolic -shared -Wl,-export-dynamic -Wl,-soname,$(SONAME)
   LDLIBS += -L${LOCALBASE}/lib -lc
   ifeq ($(ARCH_DETECTED), 64BITS)
@@ -171,6 +172,7 @@ endif
 ifeq ($(OS), LINUX)
   TARGET = libmupen64plus$(POSTFIX).so.2.0.0
   SONAME = libmupen64plus$(POSTFIX).so.2
+  CFLAGS += -DHAVE_MMAP
   LDFLAGS += -Wl,-Bsymbolic -shared -Wl,-export-dynamic -Wl,-soname,$(SONAME)
   LDLIBS += -ldl
   # only export api symbols
@@ -187,6 +189,7 @@ ifeq ($(OS), OSX)
   OSX_SDK_PATH = $(OSX_SDK_ROOT)/$(shell ls $(OSX_SDK_ROOT) | tail -1)
 
   TARGET = libmupen64plus$(POSTFIX).dylib
+  CFLAGS += -DHAVE_MMAP
   LDFLAGS += -framework CoreFoundation -dynamiclib
   LDLIBS += -ldl
   ifeq ($(ARCH_DETECTED), 64BITS)

diff --git a/src/api/frontend.c b/src/api/frontend.c
@@ -35,6 +35,7 @@
 #include "m64p_config.h"
 #include "m64p_frontend.h"
 #include "m64p_types.h"
+#include "device/memory/memory.h"
 #include "main/cheat.h"
 #include "main/eventloop.h"
 #include "main/main.h"
@@ -93,7 +94,7 @@ EXPORT m64p_error CALL CoreStartup(int APIVersion, const char *ConfigPath, const
         return M64ERR_INTERNAL;
 
     /* allocate base memory */
-    g_mem_base = malloc(0x20000000);
+    g_mem_base = init_mem_base();
     if (g_mem_base == NULL) {
         return M64ERR_NO_MEMORY;
     }
@@ -122,7 +123,7 @@ EXPORT m64p_error CALL CoreShutdown(void)
     SDL_Quit();
 
     /* deallocate base memory */
-    free(g_mem_base);
+    release_mem_base(g_mem_base);
     g_mem_base = NULL;
 
     l_CoreInit = 0;

diff --git a/src/device/memory/memory.c b/src/device/memory/memory.c
@@ -201,3 +201,82 @@ void map_region(struct memory* mem,
         mem->handlers[region] = *handler;
     }
 }
+
+
+
+#include "device/device.h"
+
+#if defined(_WIN32)
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#elif defined(HAVE_MMAP)
+#include <sys/mman.h>
+#else
+#include <stdlib.h>
+#endif
+
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof((x)[0]))
+
+enum { MEM_BASE_SIZE = 0x20000000 };
+enum { RAM_MAX_SIZE  = 0x00800000 };
+enum { ROM_MAX_SIZE  = 0x04000000 };
+
+void* init_mem_base(void)
+{
+    void* mem;
+    size_t m;
+
+    struct {
+        uint32_t begin;
+        size_t size;
+    } mappings[] = {
+        { MM_RDRAM_DRAM, RAM_MAX_SIZE }, // FIXME: use real dram_size
+        { MM_RSP_MEM,    0x00002000 },
+        { MM_DD_ROM,     0x00800000 },
+        { MM_CART_ROM,   ROM_MAX_SIZE }, // FIXME: use real rom_size
+        { MM_PIF_MEM,    0x00000800 },
+    };
+
+#if defined(_WIN32)
+    mem = VirtualAlloc(NULL, MEM_BASE_SIZE, MEM_RESERVE, PAGE_READWRITE);
+
+    for (m = 0; m < ARRAY_SIZE(mappings); ++m) {
+        if (VirtualAlloc((unsigned char*)mem + mappings[m].begin, mappings[m].size, MEM_COMMIT, PAGE_READWRITE) != 0) {
+            DebugMessage(M64MSG_ERROR, "Failed to change memory protection.");
+            VirtualFree(mem, 0, MEM_RELEASE);
+            return NULL;
+        }
+    }
+#elif defined(HAVE_MMAP)
+    mem = mmap(NULL, MEM_BASE_SIZE, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+    if (mem == MAP_FAILED) {
+        return NULL;
+    }
+
+    for (m = 0; m < ARRAY_SIZE(mappings); ++m) {
+        if (mprotect((unsigned char*)mem + mappings[m].begin, mappings[m].size, PROT_READ | PROT_WRITE) != 0) {
+            DebugMessage(M64MSG_ERROR, "Failed to change memory protection.");
+            munmap(mem, MEM_BASE_SIZE);
+            return NULL;
+        }
+    }
+#else
+    mem = malloc(MEM_BASE_SIZE);
+    if (mem == NULL) {
+        return NULL;
+    }
+#endif
+
+    return mem;
+}
+
+void release_mem_base(void* mem)
+{
+#if defined(_WIN32)
+    VirtualFree(mem, 0, MEM_RELEASE);
+#elif defined(HAVE_MMAP)
+    munmap(mem, MEM_BASE_SIZE);
+#else
+    free(mem);
+#endif
+}
diff --git a/src/device/memory/memory.h b/src/device/memory/memory.h
@@ -122,5 +122,8 @@ void deactivate_memory_break_write(struct memory* mem, uint32_t address);
 int get_memory_type(struct memory* mem, uint32_t address);
 #endif
 
+void* init_mem_base(void);
+void release_mem_base(void* mem);
+
 #endif