From 1534f70a2d09afd68b23fc365d6e10fcb2da2e23 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Tue, 19 Jul 2022 00:03:44 +0300
Subject: [PATCH] libnx: make mmap act more like on Linux

---
 frontend/switch/sys/mman.h | 93 ++++++--------------------------------
 1 file changed, 14 insertions(+), 79 deletions(-)

diff --git a/frontend/switch/sys/mman.h b/frontend/switch/sys/mman.h
index 211e09d5..49fb4454 100644
--- a/frontend/switch/sys/mman.h
+++ b/frontend/switch/sys/mman.h
@@ -6,13 +6,8 @@ extern "C" {
 #endif
 
 #include <stdlib.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <malloc.h>
+#include <string.h>
 #include <switch.h>
-#include <stdlib.h>
-
-//#include "3ds_utils.h"
 
 #define PROT_READ       0b001
 #define PROT_WRITE      0b010
@@ -23,98 +18,38 @@ extern "C" {
 
 #define MAP_FAILED      ((void *)-1)
 
-//static void* dynarec_cache = NULL;
-//static void* dynarec_cache_mapping = NULL;
+#define ALIGNMENT       0x1000
 
-static inline void* mmap(void *addr, size_t len, int prot, int flags, int fd, off_t offset)
+static inline void *mmap(void *addr, size_t len, int prot, int flags, int fd, off_t offset)
 {
-   (void)fd;
-   (void)offset;
+    (void)fd;
+    (void)offset;
+
+    // match Linux behavior
+    len = (len + ALIGNMENT - 1) & ~(ALIGNMENT - 1);
 
-   //void* addr_out;
     Result rc = svcMapPhysicalMemory(addr, len);
     if (R_FAILED(rc))
     {
-        printf("mmap failed\n");
-        return malloc(len);
+        //printf("mmap failed\n");
+        addr = aligned_alloc(ALIGNMENT, len);
     }
 
+    if (addr)
+        memset(addr, 0, len);
     return addr;
-
-//   if((prot == (PROT_READ | PROT_WRITE | PROT_EXEC)) &&
-//      (flags == (MAP_PRIVATE | MAP_ANONYMOUS)))
-//   {
-//      if(true)// __ctr_svchax)
-//     {
-//         /* this hack works only for pcsx_rearmed */
-//         uint32_t currentHandle;
-//
-//         if(!dynarec_cache)
-//            dynarec_cache = memalign(0x1000, len);
-//
-//         //svcDuplicateHandle(&currentHandle, 0xFFFF8001);
-//         //svcControlProcessMemory(currentHandle, addr, dynarec_cache,
-//         //                        len, MEMOP_MAP, prot);
-//         svcCloseHandle(currentHandle);
-//         dynarec_cache_mapping = addr;
-//         return addr;
-//      }
-//      else
-//      {
-//         printf("tried to mmap RWX pages without svcControlProcessMemory access !\n");
-//         return MAP_FAILED;
-//      }
-//
-//   }
-
-//   addr_out = memalign(0x1000, len);
-//   if(!addr_out)
-//      return MAP_FAILED;
-//
-//   return addr_out;
-}
-
-static inline int mprotect(void *addr, size_t len, int prot)
-{
-    return 0;
-   //if(true) // __ctr_svchax)
-   //{
-   //   uint32_t currentHandle;
-   //   //svcDuplicateHandle(&currentHandle, 0xFFFF8001);
-   //   //svcControlProcessMemory(currentHandle, addr, NULL,
-   //   //                        len, MEMOP_PROT, prot);
-   //   svcCloseHandle(currentHandle);
-   //   return 0;
-   //}
-
-   //printf("mprotect called without svcControlProcessMemory access !\n");
-   //return -1;
 }
 
 static inline int munmap(void *addr, size_t len)
 {
+    len = (len + ALIGNMENT - 1) & ~(ALIGNMENT - 1);
     Result rc = svcUnmapPhysicalMemory(addr, len);
     if (R_FAILED(rc))
     {
-        printf("munmap failed\n");
+        //printf("munmap failed\n");
         free(addr);
     }
     return 0;
-//   if((addr == dynarec_cache_mapping) && true)//__ctr_svchax)
-//   {
-//      uint32_t currentHandle;
-//      //svcDuplicateHandle(&currentHandle, 0xFFFF8001);
-//      //svcControlProcessMemory(currentHandle,
-//      //                        dynarec_cache, dynarec_cache_mapping,
-//      //                        len, MEMOP_UNMAP, 0b111);
-//      svcCloseHandle(currentHandle);
-//      dynarec_cache_mapping = NULL;
-//
-//   }
-//   else
-      free(addr);
-
-   return 0;
 }
 
 #ifdef __cplusplus
-- 
2.39.5