loader: add SetExtraMemory extension

docs/modules/loader.md

@@ -62,3 +62,15 @@ TODO
 ### SM MITM Integration
 
 When the Stratosphere implementation of loader creates a new process, it notifies [sm](sm.md) through the `AtmosphereAssociatePidTidForMitm` command to notify any MITM services of new processes' identities.
+
+### IPC: AtmosphereSetExtraMemory
+
+This command is added to the [`ldr:shel`](https://reswitched.github.io/SwIPC/ifaces.html#nn::ro::detail::ILdrShellInterface) interface, and allows a client to request that a title be created with a certain amount of additional CodeStatic memory the next time it is created. This is useful for advanced homebrew loaders.
+
+The SwIPC definition for this command follows.
+```
+interface nn::ldr::detail::ILdrShellInterface is ldr:shel {
+  ...
+  [65000] AtmosphereSetExtraMemory(u64 title_id, u64 extra_memory_size);
+}
+```

stratosphere/loader/source/ldr_launch_queue.cpp

@@ -23,6 +23,12 @@
 
 static std::array<LaunchQueue::LaunchItem, LAUNCH_QUEUE_SIZE> g_launch_queue = {0};
 
+/* This state is maintained separately from the launch queue so that
+   NS can't clobber this information by clearing the launch queue
+   when the process using this extension doesn't expect it. */
+static u64 g_extra_memory_tid = 0;
+static u64 g_extra_memory_size = 0;
+
 Result LaunchQueue::add(u64 tid, const char *args, u64 arg_size) {
     if(arg_size > LAUNCH_QUEUE_ARG_SIZE_MAX) {
         return 0x209;
@@ -97,3 +103,22 @@ LaunchQueue::LaunchItem *LaunchQueue::get_item(u64 tid) {
     }
     return &g_launch_queue[idx];
 }
+
+void LaunchQueue::set_extra_memory(u64 tid, u64 extra_size) {
+    g_extra_memory_tid = tid;
+    g_extra_memory_size = extra_size;
+}
+
+u64 LaunchQueue::get_extra_memory(u64 tid) {
+    if(tid == g_extra_memory_tid) {
+        u64 size = g_extra_memory_size;
+
+        // reset extra memory state
+        g_extra_memory_tid = 0;
+        g_extra_memory_size = 0;
+
+        return size;
+    } else {
+        return 0;
+    }
+}

stratosphere/loader/source/ldr_launch_queue.hpp

@@ -39,4 +39,8 @@ class LaunchQueue {
         static int get_free_index(u64 tid);
         static bool contains(u64 tid);
         static void clear();
-};
+
+        // extra memory extension
+        static void set_extra_memory(u64 tid, u64 extra_size);
+        static u64 get_extra_memory(u64 tid);
+};

stratosphere/loader/source/ldr_process_creation.cpp

@@ -172,6 +172,11 @@ Result ProcessCreation::CreateProcess(Handle *out_process_h, u64 index, char *nc
     if (R_FAILED(rc)) {
         goto CREATE_PROCESS_END;
     }
+
+    nso_extents.total_size += 0xFFF;
+    nso_extents.total_size &= ~0xFFFULL;
+
+    nso_extents.total_size += LaunchQueue::get_extra_memory(target_process->tid_sid.title_id);
     
     /* Set Address Space information in ProcessInfo. */
     process_info.code_addr = nso_extents.base_address;

stratosphere/loader/source/ldr_shell.cpp

@@ -30,6 +30,9 @@ Result ShellService::dispatch(IpcParsedCommand &r, IpcCommand &out_c, u64 cmd_id
         case Shell_Cmd_ClearLaunchQueue:
             rc = WrapIpcCommandImpl<&ShellService::clear_launch_queue>(this, r, out_c, pointer_buffer, pointer_buffer_size);
             break;
+        case Shell_Cmd_AtmosphereSetExtraMemory:
+            rc = WrapIpcCommandImpl<&ShellService::set_extra_memory>(this, r, out_c, pointer_buffer, pointer_buffer_size);
+            break;
         default:
             break;
     }
@@ -46,3 +49,9 @@ std::tuple<Result> ShellService::clear_launch_queue(u64 dat) {
     LaunchQueue::clear();
     return {0};
 }
+
+std::tuple<Result> ShellService::set_extra_memory(u64 tid, u64 extra_size) {
+    fprintf(stderr, "Set extra memory for %zX: %zX\n", tid, extra_size);
+    LaunchQueue::set_extra_memory(tid, extra_size);
+    return {0};
+}

stratosphere/loader/source/ldr_shell.hpp

@@ -20,7 +20,9 @@
 
 enum ShellServiceCmd {
     Shell_Cmd_AddTitleToLaunchQueue = 0,
-    Shell_Cmd_ClearLaunchQueue = 1
+    Shell_Cmd_ClearLaunchQueue = 1,
+
+    Shell_Cmd_AtmosphereSetExtraMemory = 65000,
 };
 
 class ShellService final : public IServiceObject {
@@ -39,4 +41,7 @@ class ShellService final : public IServiceObject {
         /* Actual commands. */
         std::tuple<Result> add_title_to_launch_queue(u64 args_size, u64 tid, InPointer<char> args);
         std::tuple<Result> clear_launch_queue(u64 dat);
+
+        /* Atmosphere commands. */
+        std::tuple<Result> set_extra_memory(u64 tid, u64 extra_size);
 };