ELFLoader, Scheduler: Transition to use VFS

We should start to drop the old InitRD API, which only allows for files to be loaded from the initrd, and which forces pathnames to be relative (bin/init)
With VFS, we can load any kind of file from any kind of filesystem, and using paths that make sense (/bin/init)

kernel/include/sys/elf/ELFLoader.h

@@ -5,5 +5,5 @@
 namespace ELFLoader
 {
     ELFImage* load_elf_from_address(uintptr_t addr);
-    ELFImage* load_elf_from_initrd(const char* filename);
+    ELFImage* load_elf_from_filesystem(const char* filename);
 }

kernel/src/main.cpp

@@ -70,52 +70,6 @@ extern "C" void _start()
 
     kinfoln("Prepared scheduler");
 
-    /*Scheduler::add_kernel_task([]() {
-        int64_t x = 0;
-        int64_t y = 0;
-        int64_t xvel = 10;
-        int64_t yvel = 10;
-        while (1)
-        {
-            sleep(2);
-            uint32_t color = (uint32_t)Mersenne::get();
-            x += xvel;
-            y += yvel;
-            if ((x + 10) >= framebuffer0.width())
-            {
-                xvel = -xvel;
-                x = (framebuffer0.width() - 10);
-            }
-            if ((y + 10) >= framebuffer0.height())
-            {
-                yvel = -yvel;
-                y = (framebuffer0.height() - 10);
-            }
-            if (xvel < 0 && (x - 10) < 0)
-            {
-                xvel = -xvel;
-                x = 0;
-            }
-            if (yvel < 0 && (y - 10) < 0)
-            {
-                yvel = -yvel;
-                y = 0;
-            }
-            framebuffer0.paint_rect(x, y, 10, 10, Color::from_integer(color));
-        }
-    });*/
-
-    /*Scheduler::add_kernel_task([]() {
-        while (1)
-        {
-            sleep(100);
-            uint32_t color = (uint32_t)Mersenne::get();
-            framebuffer0.paint_rect(Mersenne::get() % (framebuffer0.width() - 256),
-                                    Mersenne::get() % (framebuffer0.height() - 256), Mersenne::get() % 255,
-                                    Mersenne::get() % 255, Color::from_integer(color));
-        }
-    });*/
-
     Scheduler::add_kernel_task([]() {
         while (1)
         {
@@ -124,7 +78,7 @@ extern "C" void _start()
         }
     });
 
-    Scheduler::load_user_task("bin/init");
+    Scheduler::load_user_task("/bin/init");
 
     kinfoln("Prepared scheduler tasks");
 

kernel/src/sys/elf/ELFLoader.cpp

@@ -1,6 +1,7 @@
 #define MODULE "elf"
 
 #include "sys/elf/ELFLoader.h"
+#include "fs/VFS.h"
 #include "init/InitRD.h"
 #include "log/Log.h"
 #include "memory/MemoryManager.h"
@@ -19,16 +20,37 @@ static const char* format_permissions(uint32_t flags)
     return perms;
 }
 
-ELFImage* ELFLoader::load_elf_from_initrd(const char* filename)
+ELFImage* ELFLoader::load_elf_from_filesystem(const char* filename)
 {
-    InitRD::File elf_file = InitRD::open(filename);
-    if (!elf_file.addr)
+    VFS::Node* node = VFS::resolve_path(filename);
+
+    if (!node)
     {
         kwarnln("Failed to open file %s for loading", filename);
         return 0;
     }
 
-    return load_elf_from_address((uintptr_t)elf_file.addr);
+    if (node->type == VFS_DIRECTORY)
+    {
+        kwarnln("Failed to load %s: is a directory", filename);
+        return 0;
+    }
+
+    void* file = kmalloc(node->length);
+    if (VFS::read(node, 0, node->length, (char*)file) < 0)
+    {
+        kwarnln("Failed to read ELF image from file");
+        kfree(file);
+        return 0;
+    }
+
+    ELFImage* result =
+        load_elf_from_address((uintptr_t)file); // FIXME: Read headers and sections as we go along the file, to avoid
+                                                // loading the entire file at once into memory.
+
+    kfree(file);
+
+    return result;
 }
 
 ELFImage* ELFLoader::load_elf_from_address(uintptr_t addr)

kernel/src/thread/Scheduler.cpp

@@ -117,7 +117,7 @@ void Scheduler::load_user_task(const char* filename)
     Task* new_task = new Task;
     ASSERT(new_task);
     new_task->id = free_tid++;
-    ELFImage* image = ELFLoader::load_elf_from_initrd(filename);
+    ELFImage* image = ELFLoader::load_elf_from_filesystem(filename);
     if (!image)
     {
         kerrorln("Failed to load %s from initrd", filename);