exec.c: Support huge pages on Linux.

Change-Id: I971e597c0c337657f188304ed26420be6b5d15f6
diff --git a/exec.c b/exec.c
index 47c8825..9998487 100644
--- a/exec.c
+++ b/exec.c
@@ -791,7 +791,7 @@
     qemu_mutex_unlock(&ram_list.mutex);
 }
 
-#if defined(__linux__) && !defined(CONFIG_ANDROID)
+#ifdef __linux__
 
 #include <sys/vfs.h>
 
@@ -837,7 +837,7 @@
 
     hpagesize = gethugepagesize(path);
     if (!hpagesize) {
-        return NULL;
+        goto error;
     }
 
     if (memory < hpagesize) {
@@ -846,11 +846,11 @@
 
     if (kvm_enabled() && !kvm_has_sync_mmu()) {
         fprintf(stderr, "host lacks kvm mmu notifiers, -mem-path unsupported\n");
-        return NULL;
+        goto error;
     }
 
     /* Make name safe to use with mkstemp by replacing '/' with '_'. */
-    sanitized_name = g_strdup(block->mr->name);
+    sanitized_name = g_strdup(block->idstr);
     for (c = sanitized_name; *c != '\0'; c++) {
         if (*c == '/')
             *c = '_';
@@ -864,7 +864,7 @@
     if (fd < 0) {
         perror("unable to create backing store for hugepages");
         g_free(filename);
-        return NULL;
+        goto error;
     }
     unlink(filename);
     g_free(filename);
@@ -884,7 +884,7 @@
     if (area == MAP_FAILED) {
         perror("file_ram_alloc: can't mmap RAM pages");
         close(fd);
-        return (NULL);
+        goto error;
     }
 
     if (mem_prealloc) {
@@ -913,7 +913,7 @@
         }
 
         /* MAP_POPULATE silently ignores failures */
-        for (i = 0; i < (memory/hpagesize)-1; i++) {
+        for (i = 0; i < (memory/hpagesize); i++) {
             memset(area + (hpagesize*i), 0, 1);
         }
 
@@ -928,6 +928,11 @@
 
     block->fd = fd;
     return area;
+error:
+    if (mem_prealloc) {
+        exit(1);
+    }
+    return NULL;
 }
 #else
 static void *file_ram_alloc(RAMBlock *block,