Add tmemCreateFromMemory

nx/include/switch/kernel/tmem.h

@@ -27,6 +27,16 @@ typedef struct {
  */
 Result tmemCreate(TransferMemory* t, size_t size, Permission perm);
 
+/**
+ * @brief Creates a transfer memory object from existing memory.
+ * @param t Transfer memory information structure that will be filled in.
+ * @param buf Pointer to a page-aligned buffer.
+ * @param size Size of the transfer memory object to create.
+ * @param perm Permissions with which to protect the transfer memory in the local process.
+ * @return Result code.
+ */
+Result tmemCreateFromMemory(TransferMemory* t, void* buf, size_t size, Permission perm);
+
 /**
  * @brief Loads a transfer memory object coming from a remote process.
  * @param t Transfer memory information structure which will be filled in.

nx/source/kernel/tmem.c

@@ -37,6 +37,26 @@ Result tmemCreate(TransferMemory* t, size_t size, Permission perm)
     return rc;
 }
 
+Result tmemCreateFromMemory(TransferMemory* t, void* buf, size_t size, Permission perm)
+{
+    Result rc = 0;
+
+    if (buf == NULL || ((uintptr_t)buf & 0xFFF)) {
+        return MAKERESULT(Module_Libnx, LibnxError_BadInput);
+    }
+
+    t->handle = INVALID_HANDLE;
+    t->size = size;
+    t->perm = perm;
+    t->map_addr = NULL;
+    t->src_addr = NULL;
+
+    memset(buf, 0, size);
+    rc = svcCreateTransferMemory(&t->handle, buf, size, perm);
+
+    return rc;
+}
+
 void tmemLoadRemote(TransferMemory* t, Handle handle, size_t size, Permission perm)
 {
     t->handle = handle;
@@ -64,7 +84,7 @@ Result tmemMap(TransferMemory* t)
         }
     }
     else {
-        rc = LibnxError_AlreadyMapped;
+        rc = MAKERESULT(Module_Libnx, LibnxError_AlreadyMapped);
     }
 
     return rc;